期刊
EUROPEAN JOURNAL OF PHARMACOLOGY
卷 428, 期 3, 页码 337-342出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/S0014-2999(01)01339-5
关键词
orexin A; small intestine, mouse; nonadrenergic noncholinergic (NANC) relaxation
The effect of a novel peptide, orexin A, on longitudinal muscle of ICR mouse small intestine was examined in vitro. Exogenous orexin A induced a transient contraction in duodenal, jejunal and ileal segments. Atropine and tetrodotoxin completely inhibited the contractions. Contraction of longitudinal muscle of jejunal segments induced by electrical field stimulation was still observed after the jejunal segment had been desensitized to orexin A, suggesting that orexin A is not a final neurotransmitter to induce the contraction. On the other hand, in the presence of atropine and guanethidine, orexin A induced a transient gradual relaxation in duodenal, jejunal and ileal segments. Electrical field stimulation also induced significant relaxation of the muscle in jejunal segments. The electrical field stimulation-induced relaxation was inhibited by 55% after the desensitization of the segments to orexin A. Although the electrical field stimulation-induced relaxation was inhibited by 47% by a nitric oxide synthesis inhibitor, NG-nitro-L-arginine (L-NOARG), orexin desensitization did not affect the relaxation which persisted after L-NOARG treatment. The exogenous orexin A-induced relaxation was completely inhibited by L-NOARG. The results suggest that orexin A partially mediates nonadrenergic, noncholinergic (NANC) relaxation via activation of nitrergic neurones in longitudinal muscle of ICR mouse small intestine. (C) 2001 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