| Project/Area Number |
17590116
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Medical pharmacy
|
|---|
| Research Institution | Josai International University, |
|---|
Principal Investigator |
HORIE Shunji Josai International University, Faculty of Pharmaceutical Sciences, Professor,, 薬学部, 教授 (50209285)
|
|---|
| Project Period (FY) |
2005 – 2006
|
| Project Status |
Completed (Fiscal Year 2006)
|
| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2006: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2005: ¥2,300,000 (Direct Cost: ¥2,300,000)
|
|---|
| Keywords | TRPV1 / Capsaicin / Gastrointestinal Frmction / TRPA1 / Immunohistochemistry / CGRP / visceral afferent / hyperesthesia |
|---|
| Research Abstract |
It is known that stress induces disorder of gastrointestinal function, but the mechanism remains to be clarified. I studied the involvement of the function and the distribution of hot receptor TRPV1 and cold receptor TRPA1 in rodents. As a result of this project, I got the following results.
(1) Intestinal motility via TRPV1: In normal mouse isolated colon and rectum, capsaicin, an agonist of TRPV1, induced transient relaxation followed by transient contraction. Subsequently long-lasting contraction appeared. Meanwhile, in transverse and proximal colon, only transient contraction was observed after application of capsaicin. The reactivity to capsaicin in rectum and distal colon is more sensitive than that in transverse and proximal colon.
(2) Influence of neonatal maternal separation stress on capsaicin-induced motility: The stress slightly augmented the capsaicin-induced transient relaxation and contraction in rectum and distal colon, but did not affect the transient contraction in transverse and proximal colon. It is suggested that stress enhances the responsiveness or the number of TRPV1 in lower gastrointestinal tract.
(3) Distribution of TRPV1 in stomach: Numerous TRPV1-immunoreactive axons were found around arterioles in the submucosal layer. A large number of nerve fibers were seen in the smooth muscle layer and in the myenteric nerve plexus.
(4) Intestinal motility via TRPA1: Allyl isothiocyanate, an agonist of TRPA1, induced the enhancement of spontaneous contraction in lower intestine in normal mice, especially in rectum. This response is thought to result from the stimulation of TRPA1.
|
