Substance P: mechanism of action and receptor distribution at the feline ileocecal sphincter region.
Substance P: mechanism of action and receptor distribution at the feline ileocecal sphincter region.
复制标题
P物质:猫回盲部括约肌区域的作用机制和受体分布。
DOI:
10.1152/ajpgi.1989.257.3.g447
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发表时间:
1989
期刊:
影响因子:
--
通讯作者:
Ouyang,A
中科院分区:
文献类型:
--
作者:
Rothstein,RD;Johnson,E;Ouyang,A
The purpose of this study was to determine the mechanism of action of substance P at the distal ileum, ileocecal sphincter (ICS), and proximal colon in the cat and to determine the localization of substance P receptors at these sites by autoradiography. Intraluminal pressures and myoelectric activity were recorded at the feline distal ileum, ICS, and colon. Substance P caused a tonic and phasic spike-dependent contractile response at all three sites. The antagonists propranolol, phentolamine, and naloxone did not affect the contractile response to substance P at the ileum, ICS, or colon. The ganglionic blocker trimethaphan camsylate potentiated the response to substance P at all three sites, P less than 0.05. Both atropine and tetrodotoxin reduced the response of substance P at the ileal site. At the ICS, atropine or tetrodotoxin reduced, but did not obliterate, the effect of substance P. Neither atropine nor tetrodotoxin reduced substance P-induced colonic contractions. By use of autoradiography, specific binding for substance P was determined to be present at all three sites with the greatest concentration of substance P receptors in the circular muscle layer. In conclusion, these studies suggest multiple sites of action of substance P. At the ileum, substance P causes contraction via a cholinergic pathway. At the ICS, substance P has an excitatory action through a cholinergic pathway and also at smooth muscle receptors. In the proximal colon, the excitatory action of substance P is via smooth muscle receptors. An inhibitory ganglionic pathway also exists at all three sites. Substance P receptors exist predominantly in the circular muscle region of the ileum, ICS, and the proximal colon.
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影响因子:
3.5
作者:
Francis L. Marcrina;R. Evans;J. A. Tobian;D. Hartley;D. Clewell;K. Jones
通讯作者:
Francis L. Marcrina;R. Evans;J. A. Tobian;D. Hartley;D. Clewell;K. Jones
影响因子:
3.2
作者:
REEVE, JN;MENDELSO.NH;COLE, RM
通讯作者:
COLE, RM
影响因子:
2.9
作者:
CURRIER, TC;NESTER, EW
通讯作者:
NESTER, EW
影响因子:
3.5
作者:
Martinez,S;Lopez,P;Espinosa,M;Lacks,SA
通讯作者:
Lacks,SA
影响因子:
3.5
作者:
Keith C. Backman;Herbert W. Boyer
通讯作者:
Herbert W. Boyer