OBJECTIVE: To determine the effect of the area postrema (AP) of the medulla oblongata on gastrointestinal interdigestive migrating motor complex (MMC) and the plasma motilin level. METHODS: Interdigestive MMC activiti...OBJECTIVE: To determine the effect of the area postrema (AP) of the medulla oblongata on gastrointestinal interdigestive migrating motor complex (MMC) and the plasma motilin level. METHODS: Interdigestive MMC activities of the antrum and duodenum were recorded by strain gauge implanted on the serosa of 8 conscious dogs. A cannula was intubated in femoral vein for motilin injection. The plasma motilin concentration was measured by RIA. We observed: (1) normal interdigestive MMC activity and fluctuations in plasma motilin concentration; (2) the effects of electrically damaging the AP on MMC activity and plasma motilin level; (3) whether intravenous injection of motilin could induce phase III contractions after the AP was destroyed. RESULTS: (1) Typical interdigestive MMC with phase I, II, III, and IV was recorded in normal dogs. Phase III was concurrent with the peak of plasma motilin level. (2) In damaged AP dogs, 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. CONCLUSIONS: The area postrema might play an important role, which is mediated by motilin, on the regulation of interdigestive MMC.展开更多
Since 1990, a series of studies on rats, monkeys and human foetus showed that an arcshaped zone is present in the middle-caudal segment of medulla oblongata, running from the dorsomedial part to the ventrolateral part...Since 1990, a series of studies on rats, monkeys and human foetus showed that an arcshaped zone is present in the middle-caudal segment of medulla oblongata, running from the dorsomedial part to the ventrolateral part and passing through the reticular formation. It was named the medullary visceral zone (MVZ). The MVZ has been investigated with various techniques (Golgi method, Nissl method, immunohistochemical method, in situ hybridization method, triple labelling method, neurophysiological method, etc. ), and the morphological features as well as the physiological functions of MVZ have been preliminarily understood. It is proved that the medullary life center is located in MVZ.An introduction and some comments are given on the location of MVZ, its shape and extent, cytoarchitecture, and chemicoarchitecture, afferent and efferent fiber connections and their functions, and its important physiological functions.展开更多
基金supported by the National Climbing Program (No.95-Ⅷ-19-222); the National Natural science Foundation of China(No.39770285)
文摘OBJECTIVE: To determine the effect of the area postrema (AP) of the medulla oblongata on gastrointestinal interdigestive migrating motor complex (MMC) and the plasma motilin level. METHODS: Interdigestive MMC activities of the antrum and duodenum were recorded by strain gauge implanted on the serosa of 8 conscious dogs. A cannula was intubated in femoral vein for motilin injection. The plasma motilin concentration was measured by RIA. We observed: (1) normal interdigestive MMC activity and fluctuations in plasma motilin concentration; (2) the effects of electrically damaging the AP on MMC activity and plasma motilin level; (3) whether intravenous injection of motilin could induce phase III contractions after the AP was destroyed. RESULTS: (1) Typical interdigestive MMC with phase I, II, III, and IV was recorded in normal dogs. Phase III was concurrent with the peak of plasma motilin level. (2) In damaged AP dogs, 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. CONCLUSIONS: The area postrema might play an important role, which is mediated by motilin, on the regulation of interdigestive MMC.
文摘Since 1990, a series of studies on rats, monkeys and human foetus showed that an arcshaped zone is present in the middle-caudal segment of medulla oblongata, running from the dorsomedial part to the ventrolateral part and passing through the reticular formation. It was named the medullary visceral zone (MVZ). The MVZ has been investigated with various techniques (Golgi method, Nissl method, immunohistochemical method, in situ hybridization method, triple labelling method, neurophysiological method, etc. ), and the morphological features as well as the physiological functions of MVZ have been preliminarily understood. It is proved that the medullary life center is located in MVZ.An introduction and some comments are given on the location of MVZ, its shape and extent, cytoarchitecture, and chemicoarchitecture, afferent and efferent fiber connections and their functions, and its important physiological functions.