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| Neuroscience, 1982 Apr, 7(4), 1023 - 36 Effects of x-irradiation on axonal sprouting induced by botulinum toxin; Gomez S et al.; The effect of X-irradiation on axonal sprouting of motor nerves induced by botulinum toxin was examined . Muscles of one leg in the mouse were X-irradiated (15 Gy) prior to the injection of a locally paralysing dose of botulinum toxin . It was found that axonal sprouting occurred as expected, but the sprouts remained unmyelinated and many degenerated . Fewer new end-plates were formed, muscles remained more severely atrophied and supersensitive to acetylcholine and recovery of neuromuscular transmission was greatly delayed when compared with the effects of botulinum toxin alone . The experiments show that X-irradiation did not prevent sprouting but, probably by impairing Schwann cell proliferation, altered axon-Schwann cell relationships and prevented the maturation of newly-formed axons and the differentiation of new end-plates. Biull Eksp Biol Med, 1982 Apr, 93(4), 13 - 5 {Role of the parasympathetic nervous system in cell proliferation of the corneal epithelium of rats after submandibular gland injury}; Denisov AB et al.; A study was made of the effect of cholinergic nerves on proliferation of epithelial cells of the cornea . Two series of experiments on 89 anesthetized Wistar rats were made to define that the blockade of the cholinergic neurons with botulinum toxin and that of tissue M-cholinoreceptors with atropine increased the mitotic index . Upon formation of humoral growth stimulators during submaxillary gland injury (SGI), the stimulating effect of atropine was further potentiated . At the same time stimulation of M-cholinoreceptors with pilocarpine lowered the magnitude of the mitotic index of the cornea cells . During SGI injury administration of pilocarpine noticeably decreased the proliferation rate . Thus the stimulation of cholinergic innervation inhibited the rate of tissue proliferation . It is suggested that during operations on the internal organs and vegetative dystonia the proliferation pattern of the cornea cell might vary which should be taken into consideration in experimental and clinical studies. Zh Mikrobiol Epidemiol Immunobiol, 1982 Apr, (4), 77 - 81 {Characteristics of the activation of type E . Cl . botulinum toxins}; Levdikova GA et al.; Molecular changes occurring in type E . Cl . botulinum single-chain toxin as the result of treatment with trypsin under different conditions were studied . The intensity of activation of the precursor and the ensuing changes of its molecular structure were found to depend on the pH of the medium . At pH 6.0 complete activation induced by the trypsin treatment of the single-chain toxin coincided with complete break-up of the polypeptide chain, while at pH 5.0 the toxin was completely activated before all its molecules could acquire the double-chain structure . At pH 4.5 no increase in the potency of the toxin was registered even in those cases when break-up of the molecules was as pronounced as by the moment of complete activation of the toxin at pH 5.0 . These data suggest that activation is not direct consequence of break-up of the peptide bond responsible for the formation of a double-chain molecule . Trypsin-induced activation seems to be linked with the splitting of some peptide bond in one of the end areas of the molecule. Neuroscience, 1982 Apr, 7(4), 997 - 1006 The effects of purified botulinum neurotoxin type A on cholinergic, adrenergic and non-adrenergic, atropine-resistant autonomic neuromuscular transmission; MacKenzie I et al.; The twitch response observed during low frequency electrical stimulation of postganglionic cholinergic neurones supplying the longitudinal smooth muscle of the guinea-pig ileum was markedly reduced by incubation with an homogeneous preparation of botulinum type A neurotoxin (4.3-8.6 nM) . This intoxication of the autonomic cholinergic neurones was long-lasting, irreversible by washing, but readily reversed by 4-aminopyridine (50-1000 microM) . The noradrenergic motor response of the rat anococcygeus following field stimulation was partially antagonised by the neurotoxin . The non-adrenergic inhibitory response of the guinea-pig taenia coli, elicited by field stimulation, was not antagonised by botulinum toxin, suggesting that a source of a non-adrenergic inhibitory transmitter exists, other than intramural cholinergic neurones . However, the neurogenic excitatory responses of the guinea-pig bladder, elicited by field stimulation in the presence of atropine and guanethidine, were virtually abolished by botulinum toxin . It is suggested that the parasympathetic neurones which supply the smooth muscle of the guinea-pig urinary bladder co-release acetylcholine and a non-cholinergic excitatory transmitter; ATP or polypeptides are possible candidates. Proc R Soc Lond B Biol Sci, 1982 Jan 22, 214(1195), 229 - 44 4-aminoquinoline-induced 'giant' miniature endplate potentials at mammalian neuromuscular junctions; Molgo J et al.; 4-Aminoquinoline (4-AQ) in concentrations around 200 micrometers induces, within minutes of its application to isolated mouse or rat neuromuscular junctions, the appearance of a population of miniature endplate potentials (m.e.p.ps) with a larger than normal amplitude, so-called giant m.e.p.ps (g.m.e.p.ps) . With amplitudes 2-12 times the modal value of m.e.p.p . amplitude, the population of g.m.e.p.ps varied between 15 and 45% of the total population of m.e.p.ps . There was no increase in the frequency of m.e.p.ps but a positive correlation between the frequency of g.m.e.p.ps and the total frequency of m.e.p.ps . In many instances the rise time and decay time of g.m.e.p.ps were prolonged compared to normal . Elevated extracellular calcium concentrations increased the frequency of m.e.p.ps but had no effect on g.m.e.p.p . frequency . High extracellular potassium concentrations markedly increased m.e.p.p . frequency but failed to influence g.m.e.p.p . frequency . Similar observations were made with ethanol 0.1 M, ouabain 200 micrometers or black widow spider venom . Botulinum toxin type A markedly reduced total m.e.p.p . frequency but 4-AQ still induced g.m.e.p.ps . Nerve stimulation failed to release quanta corresponding to the g.m.e.p.ps . G.m.e.p.ps seemed to originate from quantal acetylcholine release from the nerve terminal since they were abolished by surgical denervation and by the addition of d-tubocurarine to the medium . Blockade of voltage-sensitive calcium or sodium channels by, respectively, manganese ions or tetrodotoxin failed to affect the appearance and the frequency of g.m.e.p.ps . The electrophysiological findings and a statistical analysis of the characteristics of the m.e.p.ps indicate that they belong to two populations . One population is accelerated by the depolarization-release coupling mechanism responsible for evoked transmitter release and is characterized by an amplitude distribution and a process in time that indicate that they correspond to releases occurring at 'active zones' in the nerve terminal . The second population of m.e.p.ps is uninfluenced by nerve terminal depolarization and transmembrane calcium fluxes . This population apparently originates from sites dispersed in the nerve terminal membrane and outside the 'active zones' . 4-AQ increases the frequency of this second m.e.p.p . population without affecting the first population. Neuroscience, 1982 Jan, 7(1), 37 - 44 The distribution of nodal sprouts in a paralysed or partly denervated mouse muscle; Hopkins WG et al.; The right gluteus maximus muscles of young adult mice were paralysed with botulinum toxin for up to 21 days or partly denervated by spinal root section for up to 63 days; the intramuscular and extramuscular nerves were then examined in the electron microscope in thin sections of tissue fixed conventionally or stained with zinc iodide-osmium tetroxide . Contralateral muscles were also examined as controls . The distribution of nodal sprouts in the nerves of the paralysed or partly denervated muscles was determined by calculating the mean ratios of unmyelinated to myelinated axons in nerve profiles containing different numbers of myelinated axons (intact or degenerating) and comparing these with control ratios . In paralysed muscles there was a significantly higher proportion of nerve profiles containing one or two unmyelinated axons alongside a single myelinated axon . Nerve profiles containing two or more myelinated axons did not show any increase in the proportion of unmyelinated axons . Thus, there is probably nodal sprouting in paralysed muscles which is restricted to the most distal nodes of the intramuscular nerves . In muscles partly denervated for 8 days there were significant increases in the proportion of unmyelinated axons in nerve profiles which had contained up to 5-10 myelinated axons . After 21 days of partial denervation, similar increases may have occurred in the larger intramuscular nerve profiles and after 63 days there were large increases in the proportion of unmyelinated axons in the main intramuscular nerve branches and in the extramuscular nerve . Nodal sprouting in response to partial denervation is therefore localised initially to the smaller, more distal nerve branches; at later times, some sprouts probably grow slowly in a disto-proximal direction along denervated Schwann cell pathways . The existence of nodal sprouts in paralysed muscles and their restricted distribution in paralysed and partly denervated muscles suggest that the nodal sprouting stimulus is produced by the muscle and acts only at distal nodes. Vet Med Nauki, 1982, 19(1), 57 - 63 {Production of monospecific type A botulinum toxin and antiserum using a column chromatographic method}; Marchev N et al.; A column chromatography method was employed to obtain a monospecific botulinus type A toxin . The latter was found to be a homogeneous product via column chromatographic and electrophoretic studies . The immunodiffusion test after Ouchterlony with a serum obtained with the use of a native toxin yielded one precipitation line . No such lines were produced with a serum obtained from animals immunized with a type B toxin . The purified toxin could be detoxicated by routinely applied methods . When injected to rabbits it induced the production of monospecific antibodies. Rev Argent Microbiol, 1982 Jan-Mar, 14(1), 1 - 16 {Numerical taxonomy of gram-positive anaerobic bacilli}; Rivas M et al.; Numerical Taxonomy's techniques were employed on twenty one anaerobic Gram positive bacilli strains taking account of eighty morphologic and biochemical features . Two methods of coding (weighted and non weighted) and four clustering methods (unweighted pair-group method using arithmetic averages; weighted pair-group method using arithmetic averages; single linkage and complete linkage) were used . Eight dendrograms were obtained and they showed that C . haemolyticum (strains 1, 2, 4, 7); C . subterminale (strains 8, 19); C . botulinum (strain 14) and C . sporogenes (strain 15) belong to a different group than the other strains . Another group would be formed with C . perfringens (strains 3, 5, 6, 12, 16, 21) and C . paraperfringens (strains 9, 10, 11) . Of the remaining strains the two classified as Propionibacterium acnes (strains 17, 18) have a very high degree of agreement . C . histolyticum (strain 20) adjoins at a very low level, while C . butyricum (strain 13) shows a unfixed behaviour . The dendrograms display a disposition according with Classical Taxonomy. Muscle Nerve, 1982, 5(9S), S12 - 6 Spontaneous transmitter release in experimental neuromuscular disorders of the rat; Thesleff SW; Examination of spontaneous miniature end-plate potentials (mepps) in rat skeletal muscle has revealed that in conditions such as botulinum poisoning, during nerve terminal regeneration or in the presence of the drug 4-aminoquinoline two types of acetylcholine release are responsible for the mepps . In addition to the mepps that correspond to the quantal component of a nerve impulse evoked end-plate potential, a second type of acetylcholine release occurs . The latter type of transmitter release gives rise to mepps with a more prolonged time to peak and frequently a larger than normal amplitude . It is unaffected by nerve terminal depolarization, transmembrane calcium fluxes, and other procedures known to enhance mepp frequency . In botulinum-poisoned muscles this secretory type of transmitter release dominates, being exclusively present in muscles where nerve stimulation fails to release transmitter . In normal muscle such a release is induced by 4-aminoquinoline, which may cause up to 50% of all the spontaneous mepps to be of that kind . It is suggested that the described secretion of acetylcholine serves a neurotrophic function. Toxicon, 1982, 20(3), 649 - 54 Botulinum toxin type A: kinetics of calcium dependent paralysis of the neuromuscular junction and antagonism by drugs and animal toxins; Metezeau P et al.; The effect of botulinum Toxin (BoTx), which blocks the mechanism of release of acetylcholine at neuromuscular junctions and induces paralysis of muscles stimulated by nerves, is known to be Ca2+-dependent . Amplitude of muscular contractions evoked by nerve impulse was studied in BoTx poisoned preparations . The present report notes that an increase in Ca2+ concentration in vitro delays paralysis of muscular contractions of the frog evoked by nerve impulse . The restorative effect of different drugs on this paralysis has been tested: 4-aminopyridine, ATXII (toxin isolated and purified from the sea anemone Anemonia sulcata tentacles) and a crude venom isolated from the scorpion Androctonus australis antagonize the BotX induced paralysis at physiological concentrations of Ca2+ (Cao2+ = 2 mM), whereas the restorative effect observed with tetra-ethylammonium or guanidine occurs at higher concentrations of Ca2+ (Cao2+ = 4 mM), as in mammals . ATXII restores in vivo the activity of a BoTx paralysed muscle of guinea pig and this effect is more efficient if the interval between the injection of BoTx and ATXII is shortened . These results on the frog and guinea pig are in agreement with those obtained on other biological preparations by several investigators . Moreover it is suggested that the antagonism of BoTx induced paralysis is a consequence of the increase in Ca2+ at the nerve ending . The efficiency of 4-aminopyridine and animal toxins is explained by an action on the nerve ending, by increasing Ca2+ from an interval compartment of the cell, whereas antagonism produced by guanidine and tetraethylammonium involves uptake of Ca2+ from the external medium . The bathing medium must be at a higher concentration of Ca2+ than usual . This explains the differences in antagonism obtained by these drugs and toxins in vitro and in vivo. Naunyn Schmiedebergs Arch Pharmacol, 1981 Dec, 318(2), 105 - 11 Tetanus toxin and botulinum A neurotoxin inhibit and at higher concentrations enhance noradrenaline outflow from particulate brain cortex in batch; Habermann E; Tetanus toxin and, to a lesser degree, botulinum A toxin partially depress the basal and the potassium evoked outflow of {3H}noradrenaline from preloaded particulate rat forebrain cortex . The effect is due to the toxins and not to any contaminant, as shown by dialysis, heating and antitoxin treatment, and also by replacement of crystalline botulinum A toxin with purified neurotoxin . Tetanus toxin also depresses the outflow due to sea anemone toxin II, 4-aminopyridine and d-amphetamine . The effect of the toxins proceeds with time and strongly depends on temperature . Once manifest the tetanus toxin effect is not reversed by antitoxin . Pretreatment with V . cholerae neuraminidase degrades the long-chain gangliosides quantitatively to GM1 . Tetanus toxin, applied subsequently remains fully active . High concentrations of tetanus toxin and botulinum A neurotoxin promote the outflow of small amounts of tritium within short incubation times . It is concluded: a) Tetanus toxin is a broad range neurotoxin which acts on processes subsequent to the depolarization step . b) Long-chain gangliosides are only binding sites, but not receptors of tetanus toxin . c) Botulinum A toxin is less potent but resembles tetanus toxin in both promoting and depressing the outflow of noradrenaline. Proc R Soc Lond B Biol Sci, 1981 Nov 24, 213(1193), 489 - 93 The reduction of endplate responses by botulinum toxin; Gundersen CB et al.; Endplate responses were recorded in frog muscle fibres during an advanced stage of botulinum (BoTX) paralysis, when transmitter release had fallen to a very low level . By simultaneous recording from two points, it was found that, even when the quantal responses had been reduced to less than 0.01 per impulse (that is, four to five orders of magnitude below normal), the release continued to be spatially dispersed along the terminal arborization . These observations make it very unlikely that whole "active zones' could be eliminated, as has been suggested, in all-or-none fashion by local action of BoTX molecules, and they suggest a more graded, indirect mechanism by which the toxin molecules interfere with the sites of transmitter release. Neurosci Lett, 1981 Nov 4, 26(3), 307 - 11 Different effects of botulinum A toxin and tetanus toxin on the transmitter releasing process at the mammalian neuromuscular junction; Dreyer F et al.; The quantal transmitter release of tetanus (TeTx) and botulinum A (BoTx) toxin paralyzed mouse diaphragms was studied . The very low release probability could be enhanced by increasing the frequency of nerve stimulation to 50 Hz or by the application of 4-aminopyridine . In the BoTx-muscles the endplate potentials were strongly coupled to the stimuli with synaptic delays similar to unpoisoned terminals . In contrast, in the TeTx-muscles large variations in the delay of release of quanta in response to stimulation were observed . From these findings it is suggested that TeTx and BoTx act at different sites of the depolarization-transmitter release process. Biull Eksp Biol Med, 1981 Nov, 92(11), 537 - 9 {Effect of cytostatics on the development of denervation disorders in skeletal muscles}; Mikhailov VV; Experiments on rats were made to study the effect of cytostatics on the rest membrane potentials (RMP) of muscle fibres and chemosensitivity of the botulinum toxin (BT) poisoned m . soleus . Intramuscular injection of the sublethal dose of BT on the 5th day evoked the blockade of the synaptic neuromuscular transmission, depolarization of the muscle cells and the decreased sensitivity to acetylcholine . Daily intraperitoneal injections of vincristine (25 micrograms/100 g) and fluorouracil (5 mg/100 g) to rats did not affect the development of the neuromuscular transmission blockade induced by BT . The cytostatics did not change the RMP of the myocytes or chemosensitivity of the normal muscles . However, both the drugs prevented the depolarization of myocytes and the decreased chemosensitivity of the muscles paralyzed with BT . It is assumed that the delayed appearance of the cytostatic-induced denervation is a consequence of the suppressed division of the satellite cells. Brain Res, 1981 Oct 5, 222(1), 125 - 8 Nerve growth from nodes of Ranvier in inactive muscle; Hopkins WG et al.; Paralysis of mouse gluteus maximus muscles with botulinum toxin not only evoked the expected sprouting from nerve terminals but also induced growth from some nodes of Ranvier close to the endplate region . This finding shows that nerve degeneration is not essential for nodal sprouting and supports the hypothesis that inactive muscle liberates a motor nerve growth factor. Q J Exp Physiol, 1981 Oct, 66(4), 525 - 32 Prolonged paralysis, caused by the local injection of botulinum toxin, fails to cause motor nerve terminal sprouting in skeletal muscle of the frog; Antony MT et al.; Injection of a sublethal dose of botulinum toxin (type D) into the cutaneous pectoris muscle of the frog caused paralysis for about three months, but in contrast to previous studies in the mammal, did not appear to cause axonal sprouting from motor nerve terminals . In frogs in which the cutaneous pectoris had been denervated by crushing its nerve, reinnervation occurred within 2--3 weeks and axonal sprouts beyond the original end-plates were often observed . When the hypoglossal nerve was implanted into the cutaneus pectoris, crushing the original nerve caused profuse axonal growth from the implanted nerve towards the denervated end-plates within one week, whereas injection of botulinum toxin had little effect . Stimulation of the implanted nerve caused contraction of those cutaneus pectoris muscles whose original nerves had been crushed, but no response to stimulation of the implanted nerve was seen in those muscles in which botulinum toxin had been injected . The failure of botulinum toxin to induce nerve sprouting and acceptance of foreign innervation in the frog may be due to the fact that activity may play a less important role in the neural control of the physiological properties of muscle in this species than in the mammal. J Physiol, 1981 Sep, 318, 365 - 73 Role of degenerating axon pathways in regeneration of mouse soleus motor axons; Brown MC et al.; 1 . The recovery of tension in mouse soleus was assayed 1-5 days after crushing the extramuscular nerve in muscles which had been previously either denervated by nerve crush, partly denervated by spinal nerve root section, or paralysed by I.M . injection of botulinum toxin . Recovery of tension following nerve crush in contralateral control muscles from the same mice was also measured . The muscles were then stained with zinc iodide-osmium and examined in the light microscope . 2 . Recovery in control muscles began at about 50 hr after crush and was nearly complete by 5 days . Recovery began at about 50 hr after crush and was nearly complete by 5 days . Recovery began about 10 hr earlier and was more rapid in muscles denervated by crushing the muscle nerve 4 days before recrushing at the same site . 3 . Paralysis 12 days earlier by intramuscular injection of botulinum toxin did not enhance recovery after nerve crush . The axons remained following partial denervation 6 days before nerve crush also regenerated at a rate similar to controls . 4 . It is concluded that (1) nerves regenerate more quickly down a pre-degenerated pathway, (2) chromatolysis does not significantly enhance reinnervation, and (3) each motor axon regenerating after a crush is constrained to follow its own denervated pathway back into the muscle . 5 . Histology was consistent with these conclusions, and also showed that end-plates in control muscles reinnervated after short periods of denervation were normal in appearance and possessed little "escaped' nerve growth . This was in contrast to end-plates which had been regenerated in muscle after a preceding nerve crush, botulinum toxin paralysis or partial denervation . This suggests that growth from nerve terminals is controlled locally within a muscle. J Physiol, 1981 Aug, 317, 487 - 95 Pre- and post-synaptic actions of botulinum toxin at the rat neuromuscular junction; Sellin LC et al.; 1 . Extensor digitorum longus muscles of rats were paralysed with local, non-lethal doses of botulinum toxin Type A (BoTx) . At 2 and 7 days after toxin injection, the nerve-muscle preparations were excised and end-plate currents analysed at 23 degrees C by dual-micro-electrode voltage clamp . 2 . At 2 days after BoTx injection, the growth time of miniature end-plate currents (m.e.p.c.s) increased from a rather narrow range with a mean of 0.59 to a mean of 1.35 ms with a large variability between m.e.p.c.s . End-plate currents (e.p.c.s) were reduced compared to unpoisoned muscle . The decay phase of m.e.p.c.s and e.p.c.s, the growth phase of e.p.c.s and the voltage sensitivity of m.e.p.c.s were unchanged . 3 . At 7 days after BoTx injection, the findings were similar to 2 days except that the time constant of the decay phase of m.e.p.c.s . and e.p.c.s . was about twice a long as normal and that the voltage sensitivity of m.e.p.c.s was increased . 4 . The acetylcholine null potential (about 0 mV) was unchanged after treatment with BoTx . 5 . The increase in the growth time of m.e.p.c.s compared to e.p.c.s following the injection of BoTx suggests that the poisoning, besides blocking quantal release, affects the time course of spontaneous but not that of evoked release . After BoTx poisoning the trans-synaptic diffusion of a majority of spontaneously released transmitter quanta seems to occur more slowly or from areas more distant from the highest concentration of the post-synaptic receptor than that of evoked release . 6 . The increase in the decay phase of m.e.p.c.s and e.p.c.s and its increased voltage sensitivity observed in muscles poisoned for 7 days with BoTx suggest that appearance at the end-plate of a population of new receptors with a prolonged ion channel opening time similar to that previously described for extrajunctional receptors after denervation and for junctional receptors during development. Can J Physiol Pharmacol, 1981 Jun, 59(6), 541 - 7 BaCl2-induced contractions in the guinea pig ileum longitudinal muscle: role of presynaptic release of neurotransmitters and Ca2+ translocation in the postsynaptic membrane; Clement JG; Early studies indicated that the baCl2-induced contractions in the guinea pig ileum longitudinal muscle strip (GPI-LMS) were, in part, neuronal in origin . However, recent studies have suggested that BaCl2-induced contractions were produced by an action directly on the smooth muscle membrane . The purpose of this study was to investigate the mechanism of the BaCl2 contractions in the GPI-LMS . Botulinum toxin (5 x 10(5) MLD/mL), which blocks the electrically induced release of acetylcholine (ACh), hemicholinium-3 (HC-3; 110 micro M), which blocks ACh synthesis, tetrodotoxin (TTX; 60 nM), which blocks Na+ channels, black widow spider venom, which depletes the presynaptic neuron of neurotransmitter, and atropine (2.9 micro M), a potent muscarinic antagonist, had no effect on the BaCl2 contractions . Densensitization of the GPI-LMS to substance P did not affect the BaCl2 contraction . In Ca2+ -free buffer the BaCl2 dose-response curve was shifted to the right . In Ca2+-free solution the time to 50% inhibiton of the contractile response to ACh (73 nM) and BaCl2 (1.16 mM) was 3.7 and 125 min, respectively . The D 600 Ic50 for ACh and BaCl2 contractions was 220 and 130 nM, respectively . In Ca2+-free buffer either EGTA (0.53 mM) or D 600 (1 micro M) were potent inhibitors of BaCl2 contractions . These results suggest that in the GPI-LMS the BaCl2 response is not mediated by a release of ACh (or substance P) because inhibitors of ACh release, synthesis, and receptors do not affect the responses . Also, the BaCl2 contraction is not due to activation of Na+ channels because TTX is without effect . The BaCl2-induced contraction appears to be mainly due to the movement of membrane bound Ca2+ through D 600 sensitive Ca2+ channels with extracellular Ca2+ and possible passage of Ba2+ ions intracellularly playing relatively minor roles. Biokhimiia, 1981 May, 46(5), 825 - 31 {Changes in biological properties of botulinum neurotoxin a induced by chemical modification of its molecule by tryptophan and tyrosine}; Shibaeva IV et al.; Using spectrophotometric titration of botulinic neurotoxin A by N-bromosuccinimide, the oxidation of one tryptophane residue was shown to induce an almost complete detoxication of the toxic protein . The conformation of the toxin molecule remained thereby unchanged, as well as the precipitation capacity of the modified toxin after oxidation of two tryptophane residues . The toxin with three or more modified tryptophane residues did not produce precipitation bands with antiserum against original toxin . Nitration of the tyrosine residues in the neurotoxin molecule with tetranitromethane gradually decreased its toxicity . All nitrous derivatives of toxin (both toxic and non-toxic ones) containing 2-18 modified tyrosine residues revealed a precipitating capacity in a reaction with antiserum against original toxin and anfragment sera . The non-toxic toxin nitrous derivatives with 15-18 modified tyrosine residues possessed partial serological affinity for original toxin in a reaction with antiserum against toxin and did not interact with antisera against toxin fragments . The conformation of molecules of toxin nitrous derivatives with 4-5 modified tyrosine residues was not changed irrespective of a 80% loss of the enzyme toxicity. Brain Res, 1981 Apr 6, 210(1-2), 145 - 51 An assessment of the spread of the signal for terminal sprouting within and between muscles; Brown MC et al.; Certain muscles of the mouse and rat have been studied in order to assess how far a signal from denervated muscle can spread to elicit terminal sprouting from intact endplates . Denervation of the muscles surrounding the rat foot 4th lumbrical muscle caused no terminal sprouting in the 4th lumbrical itself . In the hemidenervated mouse gluteus maximus terminal sprouting was restricted to the central region of the muscle where innervated and denervated fibres intermingle . There was no enhancement of such sprouting if the underlying and closely apposed gluteus medius was simultaneously denervated . Hemidenervation of the mouse diaphragm and interscutularis, where intact endplates lie near to denervated muscle fibres, produced no terminal sprouting . Hemidenervation of the mouse platysma, where intact endplates often lie adjacent to denervated muscle fibres, similarly produced no significant response . However, all muscles were capable of producing extensive terminal sprouting in response to paralysis induced by botulinum toxin . The stimulus for terminal sprouting produced by an inactive muscle fibre must therefore be effective only on the fibre's own terminal or immediately adjacent terminals. Naunyn Schmiedebergs Arch Pharmacol, 1981 Apr, 316(2), 143 - 8 Tetanus toxin and botulinum A toxin inhibit acetylcholine release from but not calcium uptake into brain tissue; Bigalke H et al.; Slices or particles from rat forebrain cortex were preloaded with {3H}choline, and the release of {3H}acetylcholine was evoked with potassium ions in a superfusion system . Release depended on the presence of calcium . 1 . Incubation of the preloaded tissue preparation for 2 h with tetanus or botulinum A toxin did not change the {3H}acetylcholine content or the ratio {3H}acetylcholine/{3H}choline . Tetanus toxin diminished, dependent on dose and time, the release of {3H}acetylcholine evoked by 25 mM K+ . It was about ten times more potent than botulinum A toxin . The effect of botulinum toxin was due to its neurotoxin content . Raising the potassium concentration partially overcame the inhibition by the toxins . Hemicholinium-3, applied to preloaded slices, left the subsequent {3H}acetylcholine release unchanged . Pretreatment of particles with neuraminidase diminished the content of long-chain gangliosides to the detection limit . Such particles remained fully sensitive to tetanus toxin, and at least partially sensitive to botulinum A toxin . 2 . The potassium or sea anemone toxin II stimulated uptake of 45Ca2+ into cortex synaptosomes or particles was not inhibited by either toxin . Both toxins appear to impede the Ca2+-dependent mobilization of an easily releasable acetylcholine pool, without inhibiting the transmembranal calcium fluxes. J Physiol, 1981 Jan, 310, 13 - 35 Beta-bungarotoxin stimulates the synthesis and accumulation of acetylcholine in rat phrenic nerve diaphragm preparations; Gundersen CB et al.; 1 . The effects of beta-bungarotoxin on acetylcholine (ACh) synthesis, tissue content and release have been studied in the rat diaphragm . A gas chromatographic mass spectrometric assay was used to measure ACh and choline . 2 . Within 30 min, beta-bungarotoxin (0.14 or 1.4 micrograms/ml.) caused a significant increase in tissue ACh content . This increase was apparent prior to the final inhibition by beta-bungarotoxin of evoked (10 Hz) ACh release . 3 . The toxin enhanced the incorporation of {2H4}Ch into {2H4}ACh in both resting and stimulated preparations . 4 . Hemicholinium-3 blocked the rise in diaphragm ACh normally produced by beta-bungarotoxin . 5 . Beta-Bungarotoxin did not directly activate choline acetyltransferase in muscle homogenates . 6 . The toxin-induced rise in tissue ACh was largely absent in Ca2+-free solutions which contained either EGTA (1 mM) or SrCl2 (2 or 10 mM) . 7 . Non-neurotoxic phospholipases A2, fatty acids and the neurotoxic phospholipase A2, notexin, did not cause ACh accumulation in the diaphragm . 8 . Beta-Bungarotoxin did not stimulate ACh synthesis in denervated muscle . 9 . The extra ACh which accumulated after beta-bungarotoxin did not contribute to enhanced release by nerve impulses even when 4-aminopyridine was added to the medium . High K+ solution and black widow spider venom were also ineffective in increasing output from toxin-treated diaphragms relative to controls that had not been treated with beta-bungarotoxin . 10 . Prior injection of a rat with botulinum toxin prevented the accumulation of ACh due to beta-bungarotoxin . Tubocurarine, however, did not antagonize beta-bungarotoxin . 11 . These data indicate that beta-bungarotoxin has a unique capacity to inhibit ACh release and stimulate ACh synthesis in diaphragm nerve endings . The results are discussed in terms of a possible action of beta-bungarotoxin to raise the level of ionized Ca in the nerve terminal cytosol. Trans Am Ophthalmol Soc, 1981, 79, 734 - 70 Botulinum toxin injection of eye muscles to correct strabismus; Scott AB; One hundred thirty-two doses of botulinum A toxin were injected into 42 humans . The effect on horizontal strabismus was uniformly beneficial, and effect lasting up to 411 days since the last injection was documented . The effect in vertical strabismus and lid retraction was beneficial, but less strongly so . No systemic effect or local complications were encountered except for effect on adjacent muscles . The drug appears to be a safe and useful therapy for strabismus. Arch Immunol Ther Exp (Warsz), 1981, 29(1), 97 - 108 Determination of botulinum toxin type by the reaction of indirect hemagglutination inhibition; Reiss J et al.; Results of investigations are reported which confirm the possibility of in vitro serological determination of the types of botulinus toxins and tracing the antigen mosaic of the preparations containing mixtures of soluble antigens of these toxins . This possibility has been opened by an appropriate combination in the arrangement of the reaction of inhibition of the antigenic indirect hemagglutination. J Cell Biol, 1981 Jan, 88(1), 160 - 71 Structural evidence that botulinum toxin blocks neuromuscular transmission by impairing the calcium influx that normally accompanies nerve depolarization; Hirokawa N et al.; Taking advantage of the fact that nerve terminal mitochondria swell and sequester calcium during repetitive nerve stimulation, we here confirm that this change is caused by calcium influx into the nerve and use this fact to show that botulinum toxin abolishes such calcium influx . The optimal paradigm for producing the mitochondrial changes in normal nerves worked out to be 5 min of stimulation at 25 Hz in frog Ringer's solution containing five time more calcium than normal . Applying this same stimulation paradigm to botulinum-intoxicated nerves produced no mitochondrial changes at all . Only when intoxicated nerves were stimulated in 4-aminopyridine (which grossly exaggerates calcium currents in normal nerves) or when they were soaked in black widow spider venom (which is a nerve-specific calcium ionophore) could nerve mitochondria be induced to swell and accumulate calcium . These results indicate that nerve mitochondria are not damaged directly by the toxin and point instead to a primary inhibition of the normal depolarization-evoked calcium currents that accompany nerve activity . Because these currents normally provide the calcium that triggers transmitter secretion from the nerve, this demonstration of their inhibition helps to explain how botulinum toxin paralyzes. Vopr Med Khim, 1980 Nov-Dec, 26(6), 813 - 7 {Effect of botulinum toxin on catecholamine concentration in different types of skeletal muscle}; Chesnokova NP et al.; Local and general forms of botulinic intoxication of the C type were characterized by an increase in content of catecholamines in various skeletal muscles--fast, slow and mixed . The increase in content of adrenaline and noradrenaline was observed in the muscles, treated with the toxin, at the preclinical period of intoxication with the subsequent elevation as pareses and paralyses developed in local intoxication . Administration of guanidine chloride, which partially prevents the block of cholinergic stimulation, was accompanied by a decrease in the content of catecholamines in various muscles especially in the slow musculus soleus. MMW Munch Med Wochenschr, 1980 Oct 3, 122(40), 1365 - 70 {Neurological symptoms in poisoning}; Neu I; Acute and chronic intoxications become manifest in primary neurological symptoms . After a definition of poisoning the autonomic, neurological and psychological disturbances are briefly discussed and the therapeutic measures presented in a table . Later, the neurological symptoms are described with reference to oberservations of cases of lead, thallium, E 605 (parathion), carbon monoxide, mercury, amphetamine and botulin poisoning . Four table and 9 figures supplement the text. Ophthalmology, 1980 Oct, 87(10), 1044 - 9 Botulinum toxin injection into extraocular muscles as an alternative to strabismus surgery; Scott AB; Sixty-seven injections of botulinum . A toxin were given to patients for correction of strabismus . No systemic complications of any kind have occurred . The maximum time of paralysis occurs four to five days following the injection, and then gradually diminishes, depending on the dose . The maximum correction of strabismus has been 40 prism diopters . The maximum follow-up following injection is six months . Injection of botulinum A toxin into extraocular muscle to weaken the muscle appears to be a practical adjunct or alternative to surgical correction. Am J Med, 1980 Oct, 69(4), 567 - 70 Hypersensitivity reactions associated with botulinal antitoxin; Black RE et al.; During an 11-year period (1967 through 1977) CDC monitored reactions of hypersensitivity to botulinal antitoxin of equine origin . Of 268 persons given botulinal antitoxin, 24 (9.0 percent) had nonfatal acute (5.3 percent) or delayed (3.7 percent) hypersensitivity reactions to a skin test or therapeutic dose . The over-all rate of reaction did not differ with the age or sex of the recipient or with the type (AB or ABE) of antitoxin administered . Serum sickness occurred significantly more frequently in persons who received more than 40 ml of serum antitoxin (p < 0.02) . The over-all reaction, rate was higher than that associated with other equine serum products and probably cannot be substantially reduced . This risk, however, would be substantially reduced if not eliminated by using botulinal immune globulin obtained from hyperimmunized human donors. Appl Environ Microbiol, 1980 Oct, 40(4), 847 - 8 Problems encountered with the capillary tube immunodiffusion method for detection of botulinal toxin; Guilfoyle DE et al.; By using antitoxin specific for the neurotoxin molecule, the capillary tube immunodiffusion method did not detect low levels of crystalline toxin . Reactions described earlier with crude toxin and less specific antitoxin were probably due to nontoxigenic botulinal antigens. J Physiol, 1980 Sep, 306, 493 - 510 Nodal and terminal sprouting from motor nerves in fast and slow muscles of the mouse; Brown MC et al.; 1 . A study of nodal and terminal sprouting in fast and slow muscles of the mouse hind limb has been made using the zinc iodide and osmium tetroxide stain . 2 . The terminal sprouting normally elicited by botulinum toxin injection can be prevented by regular and frequent direct electrical stimulation of the muscle fibres . But the number of end-plates innervated by nodal sprouts in partly denervated spinal preparations was not reduced by direct muscle stimulation . 3 . In leg muscles given varying doses of botulinum toxin the amount of terminal sprouting was linearly related to the degree of paralysis . In partly denervated muscles neither the amount of terminal sprouting nor the amount of nodal sprouting was correlated with the degree of denervation . 4 . Partial denervation causes relatively more nodal sprouting in the fast muscles peroneus tertius and extensor digitorum longus than in the slower soleus muscle, which itself has considerably more terminal sprouting than the others . The fast muscles can develop as much terminal sprouting as the soleus only in response to full paralysis with botulinum toxin . 5 . No evidence could be found for a sprouting signal generated or spreading within the spinal cord . 6 . It is concluded in confirmation of earlier work (Duchen & Strich, 1968; Brown & Ironton, 1977 a) that the source of the signal for terminal sprouting is denervated or otherwise inactivated muscle fibres, whose action is boosted by the presence of degenerating nervous tissues . It is suggested that fast muscles probably have less terminal sprouting when partly denervated than slow muscles (a) because of the longer time it takes a fast muscle to undergo the changes associated with inactivity and (b) because of their higher resistance to the effects of nerve degeneration . It does not seem that the signal for nodal sprouting comes from the muscle fibres but further experimentation is needed to establish this firmly. Vopr Med Khim, 1980 Sep-Oct, 26(5), 612 - 6 {Effect of botulinus toxin on oxygen utilization in different types of skeletal muscles}; Chesnokova NP et al.; Botulinic toxin inhibited oxygen utilization in fast, slow and mixed muscles during the paralytic step of general intoxication as well as in dynamics of local intoxication without any manifestations of hypoxic hypoxia . The data obtained suggest that the tissue hypoxia caused by botulinic toxin is not responsible for the primary impairment of innervation of the respiratory muscles and for insufficiency of the outer respiration. Biokhimiia, 1980 Sep, 45(9), 1589 - 96 {Isolation and characterization of the polypeptide fragments obtained by limited proteolysis of botulinic toxin type A}; Shibaeva IV et al.; A limited proteolysis of the botulinic toxin of A type by subtylopeptidase A resulted in two high molecular weight non-toxic fragments . The peptide with mol . weight of 100,000 is made up of two subunits with mol . weights of 52,000 and 48,000 . The second peptide whose mol . weight is 40,000 is a single-chained one . The high molecular weight peptide has one S--S bond and two SH-groups, whereas the one with a lower molecular weight--no S--S bond and 1.3--1.5 SH-groups . Dansylation of the first fragment revealed two N-terminal amino acids (histidine, arginine) in toxin, which suggests the localization of the first fragment at the N-end of the toxin molecule . Using immunochemical analysis with monospecific antiserum against original toxin and antifragment sera, the antigenic determinants from the fragments were shown to be serologically different . A structural model of botulinic toxin of A type is proposed. Zh Mikrobiol Epidemiol Immunobiol, 1980 Sep, (9), 86 - 91 {Production of a homogeneous Cl . botulinum type B neurotoxin}; Saprykina TP et al.; The method for obtaining the neurotoxin, or alpha-fraction of the toxin, of Cl . botulinum, type B, is described . In accordance with this method, the toxin was precipitated three times with hydrochloric acid in the isoelectric zone with subsequent extraction with phosphate (pH 6.8) and citrate-phosphate (pH 5.6) buffers, then fractionated in columns with DEAE cellulose (pH 5.6), DEAE Sephadex A-50 (pH 7.2) and Sephadex G-200 (pH 7.2) . The homogeneous neurotoxin preparations with molecular weights ranging from 145,000 to 160,000 and having the isoelectric point at pH 5.5 and toxicity 5.0--10.0 x 10(7) Dlm per 1 mg protein were obtained. Biull Eksp Biol Med, 1980 Jul, 89(7), 25 - 7 {Mechanisms of neuro-tropic disorders induced in skeletal muscles by botulinum toxin}; Mikhailov VV; The relationship between activation of cell nucleus division and disturbances of electrogenesis of skeletal muscle fibers which had been paralyzed by botulinum toxin was studied in experiments on rats . On the 5th day after its intramuscular injection botulinum toxin evoked depolarization of muscle fibers and appearance of local responses in addition to break action potentials (AP) in most of the fibers . Inhibition of DNA synthesis by daily intraperitomeal injection of fluorouracil prevented the decreasing of rest membrane potentials and appearance of anode break AP. Appl Environ Microbiol, 1980 Jun, 39(6), 1096 - 9 Antibotulinal efficacy of sulfur dioxide in meat; Tompkin RB et al.; The addition of sodium metabisulfite as a source of sulfur dioxide delayed botulinal outgrowth in perishable canned comminuted pork when it was temperature abused at 27 degree C . The degree of inhibition was directly related to the level of sulfur dioxide . Levels greater than 100 microgram of sulfur dioxide per g were necessary to achieve significant inhibition when a target level of 100 botulinal spores per g was used . Sodium nitrite partially reduced the efficacy of the sulfur dioxide . Sulfur dioxide offers a new option for the control of botulinal outgrowth in cured or noncured meat and poultry products. J Physiol, 1980 Jun, 303, 23 - 31 Effects of denervation and botulinum toxin on muscle sensitivity to acetylcholine and acceptance of foreign innervation in the frog; Antony MT et al.; 1 . The effects of denervation and local paralysis produced by botulinum toxin (type D) on the sensitivity of skeletal muscle to ACh and its ability to accept innervation by an implanted foreign nerve were investigated in the frog . 2 . Denervated muscles developed supersensitivity to ACh within 2 weeks and became extensively innervated by an implanted foreign nerve after about 4 weeks . 3 . Chronic electrical stimulation of denervated muscles (50 Hz for 1 sec every 60 sec) did not prevent the development of supersensitivity . 4 . Muscles paralysed by botulinum toxin did not usually develop supersensitivity to ACh until after 2-3 months and the extra-junctional sensitivity of individual fibres was generally less than after denervation . Significant innervation of the paralysed muscles by an implanted foreign nerve did not occur until after 2-3 months . 5 . The results suggest that in the frog nerves are able to control muscle sensitivity to ACh and to prevent innervation by foreign nerves by some mechanism other than muscle activity . Prolonged inactivity seems to result in some development of extra-junctional sensitivity and acceptance of foreign innervation. Brain Res, 1980 Mar 17, 186(1), 21 - 32 Cytophotometric quantification of retrograde axonal transport of a fluorescent tracer (primuline) in mouse facial neurons; Enerback L et al.; A method for cytophotometric quantifications of retrograde axonal transport of a fluorescent tracer in tissue sections is described . As a fluorescent tracer the anionic vital stain primuline proved to be suitable since it resulted in a strong yellow-green fluorescence, which faded very slowly permitting localization of cells during illumination with UV-light . Primuline injected into the muscles of the vibrissae in mice was transported to the corresponding nerve cell bodies in the facial nucleus, where it appeared as fluorescent granules 9 h after the injection . The fluorescence intensity increased with increasing exposure times and concentrations of the injected tracers . The motor endplates showed no ultrastructural changes after the tracer injections . The motor endplates showed no ultrastructural changes after the tracer injections . With this method a substantial increase in tracer accumulation in facial neurons could be revealed during nerve regeneration 11 days after crushing the facial nerve . Small alterations in neuronal tracer accumulation could be measured after intoxication of the mice with botulinum and tetanus toxins . Since these toxins should cause a decrease or increase in the degree of synaptic activity the amount of retrograde axonal transport may to a certain extent be dependent on the synaptic function . The findings with this new technique therefore indicate that quantitative changes occur in axonal transport in materials from the periphery during different pathological and physiological conditions, which may be important for an understanding of how a nerve cell body is dependent on its peripheral field of innervation. Biull Eksp Biol Med, 1980 Mar, 89(3), 276 - 8 {Mechanism of disorders in neurotrophic regulation of the level of striated skeletal muscle polarization by botulinum toxin}; Mikhailov VV; Muscle reinnervation was studied in experiments on rats given intramuscular injection of sublethal doses of botulinum toxin . It has been established that botulinum toxin not influencing the formation of functioning myoneural synapses leads to long-term persistence of depolarization of reinnervated muscle cells without changes in passive biophysical properties of their sarcoplasmatic membranes. Nature, 1980 Feb 21, 283(5749), 774 - 6 Black widow spider toxin-induced calcium fluxes and transmitter release in a neurosecretory cell line; Grasso A et al.; Several polypeptide neurotoxins affect presynaptic functions by interfering with chemical neurotransmission . This group of toxins includes botulinum toxin, tetanus toxin, beta-bungaro-toxin and black widow spider toxin (BWSTx) . While the effect of the first three toxins is mainly a rapid and severe block of neurotransmitter release, BWSTx affects transmission by a massive stimulation of mediator release . Despite various hypotheses put forward to explain the action of BWSTx at the level of nerve terminals, there is still a considerable degree of uncertainty as to the cation dependence of venom action . Study of the toxin mode of action at the biochamical level has been hampered by the complexity and cellular heterogeneity of the preparations used, neuromuscular junction or synaptosomes . PC12 cell line, derived from a rat phaeochromocytoma, seems to be an excellent model in view of its property of synthesising and storing noradrenaline, dopamine and acetylcholine, and releasing them in depolarising conditions . We have recently shown that highly purified BWSTx stimulates secretion from PC12 cells of previously taken up radioactive dopamine (DA) and noradrenaline (NA) (ref . 14 and manuscript in preparation) . We report here that the earliest detectable event after toxin treatment of such cells is a massive increase of cytosolic calcium. Can J Physiol Pharmacol, 1980 Jan, 58(1), 88 - 92 Lack of effect of botulinum toxin on nonadrenergic, noncholinergic inhibitory responses of the guinea pig fundus in vitro; Paul ML et al.; The nonadrenergic, noncholinergic inhibitory (NAI) response of guinea pig fundic strip to electrical field stimulation was examined in the presence of botulinum toxin and tetrodotoxin . Tetrodotoxin completely abolished the NAI response while botulinum toxin did not alter it . It is concluded that the mediator of NAI responses is unlikely to be released with acetylcholine from cholinergic nerves or that such release would have to occur by a mechanism resistant to botulinum toxin. Vopr Med Khim, 1980 Jan-Feb, 26(1), 32 - 6 {Mechanism of the disturbance in muscle energy allowance in botulin poisoning}; Chesnokova NP et al.; Development of botulinic pareses of cat sceletal muscles was followed by an inhibition of oxygen utilization simultaneously with a still sufficient compensation of external respiration impairment . The inhibitory effect of botulinic toxins on tissue respiration was apparently mediated via impairment of cetecholamine metabolism; utilization of O2 in the muscles was unaltered during the preclinical period of the toxin intensive sorption by tissues . Also a definite relationship was observed between the development of tissue hypoxia and an increase in content of tissue catecholamines . Stimulation of tissue hypoxia was accompanied by impairments in glycolytic process, deficiency of potassium, ascorbic acid and phosphocreatine in muscle tissue. J Pediatr Ophthalmol Strabismus, 1980 Jan-Feb, 17(1), 21 - 5 Botulinum toxin injection into extraocular muscles as an alternative to strabismus surgery; Scott AB; Fifty-six injections of botulinum A toxin have been given to humans for correction of strabismus . The paralysis has been localized to the injected muscle in all cases . No systemic complications of any kind have ensued . The maximum time of paralysis occurs four to five days following the injection, and then gradually diminishes, depending on dose . The maximum correction of strabismus has been 40 prism diopters . The maximum follow-up after injection is six months . Injection of botulinum A toxin into extraocular muscle to weaken the muscle appears to be a practical adjunct or alternative to surgical correction. J Hyg Epidemiol Microbiol Immunol, 1980, 24(1), 29 - 35 Experimental study of skin-sensitizing antibodies after aerosol and subcutaneous immunization; Yefremova VN; The reaction of passive skin anaphylaxis was used to investigate the accumulation and the dynamics of skin-sensitizing antibodies (SSA) in the sera of guinea pigs immunized with botulin anatoxin by means of different methods: the aerosol and the subcutaneous method . In the aerosol-immunized animals (unlike the subcutaneously immunized ones) SSA appeared in a negligible amount only after the fourth immunization and disappeared rapidly. J Pharmacol Exp Ther, 1980 Jan, 212(1), 16 - 21 Kinetic studies on the interaction between botulinum toxin type A and the cholinergic neuromuscular junction; Simpson LL; Botulinum toxin-induced paralysis of neuromuscular transmission involves at least three steps . There is an initial binding step that is nontoxic, a translocation step that is nontoxic and a subsequent lytic step that produces blockade of transmission . In the absence of nerve stimulation, the binding step has a half-time of similar to or approximately 12 min and a rate constant of similar to or approximately 0.058 . min-1 . The binding step does not require calcium or nerve stimulation, and it has a low temperature dependence (Q10 similar to or approximately 1.6) . In the absence of nerve stimulation, the translocation step has a half-time of similar to or approximately 4.9 min and a rate constant of similar to or approximately 0.141 . min-1 . Translocation requires physiological concentrations of calcium . In the virtual absence of nerve stimulation (1 x 10(-2) Hz), the lytic step has a half-time of similar to or approximately 55 min and a rate constant of similar to or approximately 0.013 . min-1 . The lytic step requires calcium, is facillitated by nerve stimulation and has a high temperature dependence by nerve stimulation and has a high temperature dependence (Q10 similar to or approximately 4.2) . These data are used to propose a model for botulinum toxin interaction with the cholinergic nerve terminal. Zh Mikrobiol Epidemiol Immunobiol, 1979 Dec, (12), 28 - 32 {Isolation and immunochemical study of the toxic complex of Cl . botulinum type F}; Blagoveshchenskii VA et al.; The toxic comples of Cl . botulinum, type F, was separated into the toxic and nontoxic protein fractions by the methods of ion exchange chromatography and gel filtration in accordance with a specially devised purification scheme . Highly purified, electrophoretically and serologically homogeneous toxin with a molecular weight of 150,000 and potency equal to 10 X 10(6) DLM per 1 mg of protein was isolated from the toxic fraction . The nontoxic protein component had faintly pronounced hemagglutinating properties and was essentially different from type A and B hemagglutinins . The toxic complex of Cl . botulinum, type F, was shown to contain a proteolytically active fraction. Fortschr Med, 1979 Nov 1, 97(41), 1840 - 4 {Neuropharmacologic and neurotoxic studies on the Renshaw mechanism}; Hagenah R; Recurrent axon collaterals of alpha-motoneurons formed with Renshaw cells cholinergic synapses . The effects of ethanol, pyritinol-HCl and type A botulinum toxin on this central nervous cholinergic synapse were studied . Ethanol caused a marked increase in Renshaw cell activity . The excitatory influence effects above all the Renshaw cell synapses directly . Pyritinol-HCl decreased the activity of Renshaw cells . The increase of Renshaw cell activity, caused by ethanol, changed into a decrease after pyritinol-HCl application so that pyritinol-HCl has a protective effect on this cholinergic system . The injection of the neurotoxin botulinum type A into the muscle or even into the ventral root was without effect on the Renshaw cell activity during the test period . Only the direct application of botulinum toxin type A into the spinal cord led to a decrease of the early and the late response of Renshaw cells . The results are discussed and the clinical relevance is considered . The cholinergic Renshaw cell synapse is not only considered as a special synapse but also as a model for cholinergic transmission which is assumed in several parts of the central nervous system. J Comp Neurol, 1979 Sep 15, 187(2), 425 - 46 Cell death of motoneurons in the chick embryo spinal cord . IV . Evidence that a functional neuromuscular interaction is involved in the regulation of naturally occurring cell death and the stabilization of synapses; Pittman R et al.; Embryos immobilized with neuromuscular blocking agents for differing periods between 4.5 and 9 days of incubation had an increased number of motoneurons in the brachial and lumbar lateral motor columns . Treatment with alpha-cobratoxin (alpha-CTX) on days 4--9, for instance, was able to prevent virtually all natural cell death during this period; control embryos had an average of 22,500 lumbar motoneurons on day 5.5, and 13,500 on day 10, whereas treated embryos had approximately 21,000 cells on day 10 . Curare, alpha-CTX, alpha-bungarotoxin (alpha-BTX) and botulinum toxin were all about equally effective in preventing cell death . Similar treatment begun after day 12, however, had no effect on cell number . If even a partial immobilization was continued after day 10 (in embryos totally immobilized earlier) most of the excess neurons were maintained, in some cases right up to hatching, at which time the embryos died due to respiratory failure . In contrast, when administration of the immobilizing agents was stopped, allowing the embryos' motility to return to control levels, the excess neurons underwent a delayed cell death and total cell number fell to below control levels by days 16--18 . Limb muscles from embryos with excess motoneurons exhibited relatively normal differentiation and had acetylcholinesterase (AChE) stained endplates which were innervated . Following curare treatment the two wing muscles, anterior and posterior latissimus dorsi, were found to have an increased number of AChE-stained endplates, whereas the only leg muscle examined quantitatively--the ischioflexorius (IFL)--did not; the IFL, did, however, have a markedly reduced variance in endplate distance, as well as other apparent differences suggesting an altered pattern of innervation . Our findings imply that the number of motoneurons undergoing natural cell death is closely related to muscle activity . Thus, functional interactions at the developing neuromuscular junction seem to be critical in controlling cell death . If a retrograde trophic factor is involved its action is somehow related to muscle activity. Biokhimiia, 1979 Aug, 44(8), 1392 - 400 {Isolation and properties of highly purified C1 . botulinum toxin type E}; Levdikova GA et al.; A new method of isolation of highly purified Cl . botulinum toxin of E type from the cultural fluid of strain 188 centrifugates was developed . The method allows to isolate the toxin both in a precursor and in activated forms with a yield of 10--15% . The method includes fractionation by ammonium sulfate, ultrafiltration and subsequent column chromatography on DEAE-cellulose, Sephadex G-200 and DEAE-Sephadex A-50 . The preparations were found homogeneous during polyacrylamide gel electrophoresis and immunoprecipitation in agar with antitoxic horse serum . The potential specific toxicity of the preparations is 1--1,2.10(7) DLM/mg of protein . The molecular weight of the toxin is about 160 000; the molar extinction coefficient is equal to 278 nm . The isoelectric point lies around pH 6.0 . The highly purified Cl . botulinum toxin of E type was found stable upon storage. Br J Pharmacol, 1979 Jul, 66(3), 391 - 5 Contractures elicited by tetraethylammonium in avian muscle treated with methohexitone; Elliott RC; 1 The chick biventer cervicis muscle immersed in methohexitone (8.8 x 10(-5) M) responded to tetraethylammonium with contractures which were dose-related . The ED50 for tetraethylammonium was 2.1 x 10(-3) M . 2 In the absence of methohexitone, tetraethylammonium produced contractures only at much higher concentrations: these contractures were accompanied by fasciculations and neuromuscular block of the twitch fibres . 3 The contractures produced by tetraethylammonium in the presence of methohexitone were not reduced by exposure to botulinum toxin which eliminated all response of the muscle to indirect stimulation . 4 Tubocurarine (1.2 x 10(-6) M) displaced the dose-response curve for tetraethylammonium-methohexitone-induced contractures to the right . The dose-ratio was 15.63 +/- 1.98 . 5 Physostigmine (1.8 x 10(-6) M) potentiated the activity of tetraethylammonium-methohexitone 3.26 or 3.84 fold, depending on the method of calculation used . 6 Physostigmine potentiated contractures elicited by indirect repetitive stimulation 4.8 to 6.0 fold more than it potentiated contractures due to tetraethylammonium-methohexitone . 7 It is concluded that in the presence of methohexitone, tetraethylammonium produces contractures of the chick muscle by releasing acetylcholine but also by a direct agonist action on the cholinoceptor. Biull Eksp Biol Med, 1979 Jul, 88(7), 26 - 9 {Biogenic amine content and the pathomorphological shifts in different organs and tissues in a period of the hematogennic spread and fixation of botulin toxin}; Chesnokova NP et al.; In experiments on cats it was shown that 30 minutes after intravenous injection of botulinum toxin, type C, there was a fall in the catecholamine and histamine contents with a simultaneous increase of serotonin in various structures of the brain and spinal cord and in a number of inner organs as well . The metabolic changes in the biogenic amines were combined with certain pathomorphologic changes seen in the form of acute swelling, chromatolysis, destruction of some neurons of the spinal cord and brain, distrophic changes in inner organs, and an increased permeability of the blood-tissue barriers . Marked biochemical and pathomorphologic changes in the spinal cord and brain where the minimum concentration of toxin becomes manifest during its spreading allow a conclusion that botulinum neurotoxin shows its pathogenic action through a disturbed metabolism of biologically active substances. Rev Infect Dis, 1979 Jul-Aug, 1(4), 656 - 62 The action of botulinal toxin; Simpson LL; Two areas of research on botulinal toxin are reviewed: (1) isolation and characterization of the toxin molecule and (2) the mechanism by which the toxin acts to paralyze transmission by cholingerrgic nerves . The various molecules of botulinal toxin (types A, B, D, E and F) have molecular weights of approximately 150,000 . The toxins are composed of two subunits with molecular weights of approximately 100,000 and approximately 50,000, respectively . The subunits are linked by one or more disulfide bonds . The large-molecular-weight substance (approximately 150,000) is fully neurotoxic; neither subunit possesses neurotoxicity . Toxin-induced paralysis of cholingergic nerves involves three steps: (1) an initial binding step that involves an external receptor; (2) a translocation step during which the toxin molecule, or some portion of it, moves through the nerve membrane; and (3) a paralytic step during which the release of acetylcholine is blocked. Neurology, 1979 May, 29(5), 720 - 3 Cholinergic dysautonomia and Eaton-Lambert syndrome; Rubenstein AE et al.; Cholinergic autonomic function was abnormal in a 47-year-old woman with Eaton-Lambert syndrome (ELS), not associated with carcinoma . Pupillary constriction to light and accommodation, sweating, lacrimation, and salivation were all affected . There was no evidence of Sjogren syndrome or botulinum intoxication . The defect of acetylcholine release from presynaptic terminals in the Eaton-Lambert syndrome may not be restricted to the neuromuscular junction of skeletal muscle. Zh Mikrobiol Epidemiol Immunobiol, 1979 Apr, (4), 62 - 6 {Use of the passive hemagglutination inhibition reaction for the purpose of determining the antigenic activity of anatoxins in vitro}; Vorontsov IV et al.; The work deals with the study of the possibility of using the passive hemagglutination inhibition test (antibody neutralization) for the determination of the antigenic activity of botulinum toxoids, types A, B and E . Erythrocytic diagnostic preparations were shown to allow the determination of up to 0.1 g of antigen . At the same time in vitro determinations were found to satisfactorily correlate with the results of in vivo determinations of the antigenic activity of these toxoids in the antitoxin-fixation test. Zh Mikrobiol Epidemiol Immunobiol, 1978 Nov, (11), 75 - 81 {1st stage of infectious allergy}; Kravchenko AT; In administration of bacterial exotoxins (diphtheria, botulinic) to guinea pigs in doses of 1/100 Dlm at an interval of one hour there developed a typical sickness with the lethal outcome in the course of 2-3 days from the beginning of the exotoxin administration . Low bacterial exotoxin doses induced allergic reaction of the organism before the cell producing specific antibodies began to act in defence . Lymphatic system cells responded rapidly to the low doses of bacterial exotoxins, but the process of formation of cells producing antibodies failed to reach mature plasmocytes, and no antibodies formed . With increase of the interval between the administration of low bacterial exotoxin doses to 24 hours specific antibodies did form, but these antibodies failed to protect the animals which were in the state of infectious allergy . The first stage of infectious allergy induced by low bacterial doses was nonspecific . Animals which were in the state of infectious allergy to diphtheria exotoxin perished of low botulinic (exotoxin) doses, and vice versa. Brain Res, 1978 Sep 22, 153(2), 307 - 18 Effects of 4-aminopyridine on neuromuscular transmission; Lundh H; 4-Aminopyridine (4-AP) powerfully increases transmitter release from motor nerve terminals of rat and frog skeletal muscle in response to single nerve impulses . The drug also enhances transmitter release during repetitive nerve activity but, at D-tubocurarine-blocked endplates, only the first impulses cause increased transmitter release at stimulation frequencies at or above 50 Hz . At magnesium- and botulinum-poisoned endplates, 4-AP potentiates transmitter release at every stimulus during tetanic nerve stimulation and restores neuromuscular transmission . Spontaneous transmitter release in the rat is not affected by the drug, but at some frog endplates miniature endplate potential (mepp) frequency increases . The drug has no post-synaptic action, as evidenced by its lack of effect on amplitude or time course of mepps . Decreasing the temperature from 37 to 15 degrees C does not abolish the effect of 4-AP on neuromuscular transmission . In the presence of 4-AP, single nerve impulses produce repetitive spontaneous activity in the nerve terminal of the frog nerve-muscle preparation . Experiments on the mode of action of 4-AP suggest that the drug increases transmitter release by enhancing the influx of calcium ions during depolarization of the nerve terminal.
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