| Project/Area Number |
13671277
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Digestive surgery
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| Research Institution | TOHOKU UNIVERSITY |
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Principal Investigator |
FUNAYAMA Yuji Tohoku University Hospital Lecturer, 医学部附属病院, 講師 (50192315)
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| Co-Investigator(Kenkyū-buntansha) |
SHIBATA Chikaahi Tohoku University Hospital Research Associate, 医学部附属病院, 助手 (30270804)
SASAKI Iwao Tohoku University Graduate School of Medicine Professor, 大学院・医学系研究科, 教授 (60125557)
内藤 広郎 東北大学, 医学部・附属病院, 講師 (90180223)
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| Project Period (FY) |
2001 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥4,000,000 (Direct Cost: ¥4,000,000)
Fiscal Year 2002: ¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 2001: ¥1,700,000 (Direct Cost: ¥1,700,000)
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| Keywords | giant migrating contractions / yohimbine / extrinsic nerves / α2受容体 / 巨大伝播性収縮 |
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| Research Abstract |
Strain gauge force transducer to measure circular muscle activity of the gastrointestinal tract was placed on the duodenum, 2 sites in the distal ileum, and 5 sites in the colon in conscious dogs. The effect of o2 blocker yohimbine (0.5, 1.0, and 3.0 mg/kg) on ileoclonic motility and defecation was studied. We found that yohimbine induced defecations associated with giant migrating contractions (GMCs) in the ileum and colon. Although it was previously reported that GMCs accompany defecations, this is the first report that GMCs were induced by a drug. Muscarinic antagonist atropine and nicotinic antagonist hexamethonium completely abolished basal colonic motility as well as yohimbine-induced colonic contractions. Although serotonin3 receptor antagonist ondansetron inhibited yohimbine-induced colonic contractions, the degree of inhibition was not so great as atropine and hexamethonium. Opiate antagonist naloxone and neurokininl antagonist FK224 did not alter yohimbine-induced colonic contractions. The effect of yohimbine to induce GMCs and defecation was still obeserved in dogs with extrinsically denervated colon. These results indicate that the effect of yohimbine to induce GMCs and defecation was mediated via cholinergic and serotonin3 receptors, and yohimbine was considered to affect pedominantly on postsyanaptic cholinergic neurons because the effect of yohimbine was not altered by the extrinsic denervation of the colon. These findings would be of importance to think about the anti-diarrhea tretament to inhibit GMCs.
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