Participação da via nitrérgica na elevação da taxa de relaxamento transitório do esfíncter esofágico inferior decorrente da distensão retal em cães

Detalhes bibliográficos
Ano de defesa: 2011
Autor(a) principal: Palheta, Michel Santos
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Não Informado pela instituição
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: http://www.repositorio.ufc.br/handle/riufc/7625
Resumo: The rectal distension (RD) induces transitory relaxation of lower esophageal sphincter (TLERs) in dogs, this relaxation generates a drop in pressure of lower esophageal sphincter (LES) similar a intragastric pressure values event even considered the main factor for the occurrence of gastroesophageal reflux. The aim of this study was evaluate the participation of the nitrergic pathway in the increased rate of TLERs induced by rectal distension in dogs. Mongrel male dogs (n = 21) weighing 10-15 kg. The animals were fasted for 12 hours with water ad libitum. The next day, the dogs were anesthetized (ketamine 10 mg.Kg-1 + xylazine 20 mg.Kg-1). The animals were subjected to the evaluation protocol of esophageal motility during 120 min. Considering the first 30 minutes as basal period, the animals were randomly intravenous treated whit: Saline 0.15M (1ml.Kg-1, i.v.), L-NAME (3 mg.Kg-1, i.v.), L-NAME (3 mg.Kg-1, i.v.) + L-Arginine (200 mg.Kg-1, i.v.), glibenclamide (1 mg.Kg-1, i.v.) or methylene blue (3 mg.Kg-1, i.v.). After 45 min, the rectum was distended (5 ml.Kg-1, i.v.) with a latex balloon and changes in esophageal motility were recorded last 45 min. Data were analyzed using ANOVA followed by Student Newman-Keuls test. In comparison to their control animals (5,8 ± 0,34 TLESRs/h), pre-treatment with L-NAME (2,3±0,52 TLESRs/h) decreased (p <0.05) rate the TRLES induced by DR, this phenomena was reversed by L-NAME plus L-Arginine (6,5 ± 0,6 TLESRs/h, p<0,05). Moreover, the pre-treatment with methylene blue (1,56 ± 0,5 TLESRs/h) also prevent increase rate the TLESRs induced by RD. However, in animals pretreated with glibenclamide (5,3 ± 0,3 TLESRs/h) RD the showed no change in the number of TLESRs in comparison the control. Nitric oxide participates in the rising rate of TLESRs resulting from rectal distension in dogs through the cGMP second messenger