摘要
目的 :系统研究降钙素基因相关肽 (CGRP)、胃泌素 17(G17)、蛙皮素 (Bom)、甲基脑啡肽 (Met enk)、神经肽Y(NPY)和生长抑素 (SS)在中枢及外周对胃粘膜血流量 (GMBF)的影响及内源性NO在神经肽所致GMBF增加效应中的作用。方法 :采用氢气清除法测定GMBF以及近胃动脉灌注和侧脑室微量注射神经肽技术。结果 :①近胃动脉灌注CGRP和G17(5、5 0和 10 0pmol·min-1)均明显地、剂量依赖性地增加GMBF ,其中CGRP作用最强。事先静脉注射NO的生物合成阻滞剂L NAME ,可分别完全和部分阻断CGRP和G17的这一效应。②近胃动脉灌注5 0和 10 0pmol·min-1剂量的Bom和Met enk时 ,GMBF显著增加 ;L NAME可完全抑制Bom增加GMBF的效应 ,但仅部分阻断Met enk引起的效应。③近胃动脉灌注NPY(5、5 0和 10 0 pmol·min-1)可使GMBF明显降低 ,此作用具量效关系 ;SS(5 0和 10 0 pmol·min-1)亦可使GMBF明显降低。④侧脑室注射 10 μgCGRP和G17可使GMBF显著增加 ;L NAME可完全阻断CGRP的此效应 ,但仅部分阻断G17所致的GMBF增加效应。⑤侧脑室注射NPY(10 μg)可显著降低GMBF。 结论 :神经肽在大鼠GMBF的调节中具有十分重要的作用。在神经肽所致GMBF增加效应中 。
Aim: To investigate the effects of calcitonin gene-related peptide (CGR P), gastrin 17 (G 17 ), bombesin(Bom), met-enkephalin (Met-enk), neur opepti de Y (NPY) and somatostatin (SS) on GMBF and the role of endogenous NO in increa sed GMBF induced by neuropeptides in rats. Methods: By hydrogen gas clearance technique to measure gastric mucosal blood flow (GMBF) and arteria l infusion close to stomach or intracerebroventricular (icv) to microinject neu ropeptides. Results: ①Arterial infusions of CGRP and G 17 (5、50 and 100 pmol·min -1 ) increased GMBF significantly in dose-dependen t manners. CGRP had more effective effect on increasing GMBF than that of G 1 7 . Intravenous pretreatment of L-nitro-L-arginine methyl ester (L-NAME) to inhibit the synthesis of endogenous NO could abolish completely or partially t he increases in GMBF response to CGRP or G 17 respectively. ②Arterial infu sions of Bom and Met-enk (50 and 100 pmol·min -1 ) increased GMBF signifi cantly. The increases in GMBF induced by Bom or Met-enk were abolished complete ly or partially by pretreatment of L-NAME respectively.③Arterial infusion of NPY(5、50 and 100 pmol·min -1 ) led to reduction of GMBF significantly in a dose-dependent manner. SS (50 and 100 pmol·min -1 ) also reduced GMBF sig nificantly.④ icv microinjection of CGRP (10 μg) and G 17 (10 μg) increas ed GMBF significantly. The increases in GMBF induced by icv microinjection of CG RP or G 17 were blocked completely or partially respectively by pretreatmen ts with L-NAME. ⑤ icv microinjection of NPY (10 μg) decreased GMBF significan tly. Conclusion: Neuropeptides play important roles in the regulat ion of GMBF in rats and NO is involved in the increase of GMBF induced by some neuropeptides.
出处
《中国应用生理学杂志》
CAS
CSCD
北大核心
2003年第4期383-388,共6页
Chinese Journal of Applied Physiology
