期刊
EUROPEAN JOURNAL OF PHARMACOLOGY
卷 452, 期 1, 页码 105-109出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/S0014-2999(02)02300-2
关键词
orexin-A; orexin-1 receptor; SB-334867-A; acetylcholine release; tetrodotoxin
The mechanism underlying orexin-induced contraction was examined in isolated preparations of guinea pig ileum, in relation to cholinergic transmission. Orexin-A caused contraction of ileal strips in a concentration-dependent manner. 1-(2-Methylbenzoxazol-6-yl)-3[1,5]napthyridin-4-yl-urea hydrochloride (SB-334867-A) antagonized the orexin-A-induced contraction, with no effects on the acetylcholine-induced contraction and twitch contractions. The orexin-A-induced contraction was inhibited by tetrodotoxin and atropine, but not by hexamethonium, an antagonist of vasoactive intestinal peptide and a mixture of 5-hydroxytryptamine receptor antagonists. Orexin-A evoked an Outflow of [H-3]acetylcholine from the ileal strips preincubated with [H-3]choline, in a concentration-dependent manner, and the orexin-A-evoked outflow was inhibited by tetrodotoxin, indicating that the Outflow Of [H-3]acetylcholine originates from the nerve terminals. The orexin-A-evoked outflow of [H-3]acetylcholine was antagonized by SB-334867-A. Thus, orexin-A evokes the release of acetylcholine from the enteric cholinergic neurons due to stimulation of the orexin-1 receptors and then causes contractions of guinea pig ileum. (C) 2002 Elsevier Science B.V All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据