Data/hora: 08/06/2024 19:00:30

Provedor de dados: 	Journal of Venomous Animals and Toxins	
País: 	Brazil	
Título: 	Neuromuscular blocking action of the Theraphosa blondii spider venom	
Autores: 	Fontana,M. D.; Lucas,H. S. M.; Vital Brazil,O.	
Data: 	2002-01-01	
Ano: 	2002	
Palavras-chave: 	Spider venom; Mouse diaphragm preparation; Neuromuscular junction; Theraphosa blondii.	
Resumo: 	In 1919, Houssay and Negrete reported that venoms of Theraphosidae spiders induced neuromuscular blockade. In 1993, a purified toxin from Grammostola spider venom was found to block the P-type voltage-dependent calcium channel (VDCC), causing neuromuscular blockade. We studied the mode of action of Theraphosa blondii venom, a large Theraphosidae spider from Northern Brazil, Venezuela, and The Guyanas in mouse phrenic nerve-diaphragm preparation. This venom elicited a partially reversible neuromuscular blockade and did not depress directly evoked twitches or alter the membrane potential. Neostigmine produced only a poor antagonistic effect on partially blocked diaphragms. However, completely blocked miniature endplate potentials (m.e.p.ps) were reverted by neostigmine. These results can be explained by the presence of toxins in the venom that interact with the endplate receptor at the acetylcholine sites (curaremimetic toxins) and toxins that inhibit the P-type voltage-dependent calcium channel (VDCC) (omega -toxins). This study shows that Theraphosidae venoms, especially those of the Theraphosa blondii, are a source of curaremimetic toxins and omega -toxins of possible interest as tools in bioscientific research.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-79302002000200010	
Editor: 	Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP	
Relação: 	10.1590/S0104-79302002000200010	
Formato: 	text/html	
Fonte: 	Journal of Venomous Animals and Toxins  v.8 n.2 2002	
Fonte: 	info:eu-repo/semantics/openAccess