dc.creatorSerafim, FG
dc.creatorReali, M
dc.creatorCruz-Hofling, MA
dc.creatorFontana, MD
dc.date2002
dc.dateFEB
dc.date2014-11-16T12:19:43Z
dc.date2015-11-26T16:22:43Z
dc.date2014-11-16T12:19:43Z
dc.date2015-11-26T16:22:43Z
dc.date.accessioned2018-03-28T23:04:11Z
dc.date.available2018-03-28T23:04:11Z
dc.identifierToxicon. Pergamon-elsevier Science Ltd, v. 40, n. 2, n. 167, n. 174, 2002.
dc.identifier0041-0101
dc.identifierWOS:000172553800007
dc.identifier10.1016/S0041-0101(01)00217-3
dc.identifierhttp://www.repositorio.unicamp.br/jspui/handle/REPOSIP/54141
dc.identifierhttp://www.repositorio.unicamp.br/handle/REPOSIP/54141
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/54141
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1268141
dc.descriptionThe venoms of coral snakes (mainly Micrurus species) have pre- and/or postsynaptic actions, but only a few of these have been studied in detail. We have investigated the effects of Micrurus dumerilii carinicauda coral snake venom on neurotransmission in rat isolated phrenic nerve-diaphragm muscle and chick biventer cervicis preparations stimulated directly or indirectly. Al. d. carinicauda venom (5 or 10 mug/ml) produced neuromuscular blockade in rat (85-90% in 291.8 +/- 7.3 min and 108.3 +/- 13.8, respectively; n = 5) and avian (95.0 +/- 2.0 min; 5 mug/ml, n = 5) preparations. Neostigmine (5.8 muM) and 3,4-diaminopyridine (230 muM) partially reversed the venom-induced neuromuscular blockade in rat nerve-muscle preparations. In neither preparation did the venom depress the twitch response elicited by direct muscle stimulation. The contractures induced by acetylcholine in chick preparations were inhibited by the venom (95-100%; n = 4; p < 0.05). In rat preparations, the venom produced a progressive decrease in the amplitude of miniature end-plate potentials (m.e.p.ps control frequency = 69.3 +/- 5.0/ min and control amplitude = 0.4 +/- 0.2 mV) until these were abolished. Neostigmine (5.8 muM) and 3,4-diaminopyridine (230 muM) partially antagonized this blockade of m.e.p.ps. The resting membrane potential was not altered with the venom (10 mug/ml). All. d. carinicauda venom produced dose-dependent morphological changes in indirectly stimulated mammal preparations. Twenty-five per cent of muscle fibers were affected by a venom concentration of 5 mug/ml, whilst 60.7% were damaged by 10 mug of venom/ml. In biventer cervicis preparations, the morphological changes were slower in onset and were generally characterized by undulating fibers and, to a lesser extent, by zones of disintegrating myofibrils. A venom concentration of 5 mug/ml damaged 52.2% of the fibers. These findings indicate that M. d. carinicauda venom has neurotoxic and myotoxic effects and that the neuromuscular blockade involves mainly a postsynaptic action. (C) 2001 Elsevier Science Ltd. All rights reserved.
dc.description40
dc.description2
dc.description167
dc.description174
dc.languageen
dc.publisherPergamon-elsevier Science Ltd
dc.publisherOxford
dc.publisherInglaterra
dc.relationToxicon
dc.relationToxicon
dc.rightsfechado
dc.rightshttp://www.elsevier.com/about/open-access/open-access-policies/article-posting-policy
dc.sourceWeb of Science
dc.subjectblockade
dc.subjectcoral snake
dc.subjectM. d. carinicauda
dc.subjectneuromuscular junction
dc.subjecthistological changes
dc.subjectvenom
dc.titleAction of Micrurus dumerilii carinicauda coral snake venom on the mammalian neuromuscular junction
dc.typeArtículos de revistas


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