电损毁延髓最后区对犬消化间期移行性复合运动的作用

目的 探讨延髓最后区对胃肠消化间期移行性复合运动（ＭＭＣ）的影响。方法 应用８只犬进行慢性实验,在胃窦和十二指肠浆膜埋植应力传感器记录胃窦和十二指肠消化间期复合运动。在一侧股静脉内置慢性静脉托管供注外源性胃动素,用放射免疫法（ＲＩＡ）测定血浆胃动素含量。观察：（１）消化间期正常ＭＭＣ活动和血浆胃动素浓度变化;（２）电损毁延髓最后区对ＭＭＣ活动和血浆胃动素水平的影响;（３）电损毁延髓最后区对外源性胃

Effect of electrical lesion of the area postrema on gastrointestinal interdigestive migrating motor complex in conscious dogs

OBJECTIVE: To investigate the effect of area postrema (AP) of medulla oblongata on gastrointestinal interdigestive migrating motor complex (MMC). METHODS: Interdigestive MMC activity of antrum and duodenum was recorded by strain gauge implanted on the serosa in 8 conscious dogs. Cannula was intubated in the femoral vein for motilin injection. Plasma motilin concentration was measured by RIA. We observed (1) normal interdigestive MMC activity and fluctuation of plasma motilin concentration; (2) the effect of electrically destroying AP on MMC activity and plasma motilin level and (3) whether or not intravenous injection of motilin could induce phase III contractions after AP was destroyed. RESULTS: (1) Typical interdigestive MMC with phases I, II, III and IV was recorded in normal dogs. Phase III was concurrent with the peak of plasma motilin level. (2) In dogs electrically destroyed AP with antroduodenal interdigestive MMC contractions were suppressed; cyclic, phasic and migratory pattern of MMC was disrupted. Plasma motilin concentration was decreased. Intravenous injection of motilin could not induce phase III contractions. CONCLUSION: Area postrema plays an important role, which is mediated by motilin, on the regulation of interdigestive MMC.