Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/201099
Type: Artigo de periódico
Title: Neuromuscular Activity Of Micrurus Laticollaris (squamata: Elapidae) Venom In Vitro.
Author: Carbajal-Saucedo, Alejandro
Floriano, Rafael Stuani
Dal Belo, Cháriston André
Olvera-Rodríguez, Alejandro
Alagón, Alejandro
Rodrigues-Simioni, Léa
Abstract: In this work, we have examined the neuromuscular activity of Micrurus laticollaris (Mexican coral snake) venom (MLV) in vertebrate isolated nerve-muscle preparations. In chick biventer cervicis preparations, the MLV induced an irreversible concentration- and time-dependent (1-30 µg/mL) neuromuscular blockade, with 50% blockade occurring between 8 and 30 min. Muscle contractures evoked by exogenous acetylcholine were completely abolished by MLV, whereas those of KCl were also significantly altered (86% ± 11%, 53% ± 11%, 89% ± 5% and 89% ± 7% for one, three, 10 and 30 µg of venom/mL, respectively; n = 4; p < 0.05). In mouse phrenic nerve-diaphragm preparations, MLV (1-10 µg/mL) promoted a slight increase in the amplitude of twitch-tension (3 µg/mL), followed by neuromuscular blockade (n = 4); the highest concentration caused complete inhibition of the twitches (time for 50% blockade = 26 ± 3 min), without exhibiting a previous neuromuscular facilitation. The venom (3 µg/mL) induced a biphasic modulation in the frequency of miniature end-plate potentials (MEPPs)/min, causing a significant increase after 15 min, followed by a decrease after 60 min (from 17 ± 1.4 (basal) to 28 ± 2.5 (t15) and 12 ± 2 (t60)). The membrane resting potential of mouse diaphragm preparations pre-exposed or not to d-tubocurarine (5 µg/mL) was also significantly less negative with MLV (10 µg/mL). Together, these results indicate that M. laticollaris venom induces neuromuscular blockade by a combination of pre- and post-synaptic activities.
Subject: Animals
Chickens
Elapid Venoms
Elapidae
In Vitro Techniques
Male
Membrane Potentials
Mice
Muscle, Skeletal
Neuromuscular Junction
Phrenic Nerve
Receptors, Nicotinic
Synaptic Transmission
Rights: aberto
Identifier DOI: 10.3390/toxins6010359
Address: http://www.ncbi.nlm.nih.gov/pubmed/24445448
Date Issue: 2014
Appears in Collections:Artigos e Materiais de Revistas Científicas - Unicamp

Files in This Item:
File SizeFormat 
pmed_24445448.pdf657.09 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.