Data/hora: 10/06/2024 08:15:28

Provedor de dados: | 56
País: | Brazil
Título: | Participation of the NO/cGMP/K+ATP pathway in the antinociception induced by Walker tumor bearing in rats
Autores: | Barbosa,A.L.R.; Pinheiro,C.A.; Oliveira,G.J.; Torres,J.N.L.; Moraes,M.O.; Ribeiro,R.A.; Vale,M.L.; Souza,M.H.L.P.
Data: | 2012-06-01
Ano: | 2012
Palavras-chave: | Walker 246 tumor-bearing rats; Hypernociception; Nitric oxide; Carrageenan.
Resumo: | Implantation of Walker 256 tumor decreases acute systemic inflammation in rats. Inflammatory hyperalgesia is one of the most important events of acute inflammation. The L-arginine/NO/cGMP/K+ATP pathway has been proposed as the mechanism of peripheral antinociception mediated by several drugs and physical exercise. The objective of this study was to investigate a possible involvement of the NO/cGMP/K+ATP pathway in antinociception induced in Walker 256 tumor-bearing male Wistar rats (180-220 g). The groups consisted of 5-6 animals. Mechanical inflammatory hypernociception was evaluated using an electronic version of the von Frey test. Walker tumor (4th and 7th day post-implantation) reduced prostaglandin E2- (PGE2, 400 ng/paw; 50 µL; intraplantar injection) and carrageenan-induced hypernociception (500 µg/paw; 100 µL; intraplantar injection). Walker tumor-induced analgesia was reversed (99.3% for carrageenan and 77.2% for PGE2) by a selective inhibitor of nitric oxide synthase (L-NAME; 90 mg/kg, ip) and L-arginine (200 mg/kg, ip), which prevented (80% for carrageenan and 65% for PGE2) the effect of L-NAME. Treatment with the soluble guanylyl cyclase inhibitor ODQ (100% for carrageenan and 95% for PGE2; 8 µg/paw) and the ATP-sensitive K+ channel (KATP) blocker glibenclamide (87.5% for carrageenan and 100% for PGE2; 160 µg/paw) reversed the antinociceptive effect of tumor bearing in a statistically significant manner (P &lt; 0.05). The present study confirmed an intrinsic peripheral antinociceptive effect of Walker tumor bearing in rats. This antinociceptive effect seemed to be mediated by activation of the NO/cGMP pathway followed by the opening of KATP channels.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2012000600009
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2012007500047
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.45 n.6 2012
Fonte: | info:eu-repo/semantics/openAccess