Intragastric pH regulates conversion from net acid to net alkaline secretion by the rat stomach.
Intragastric pH regulates conversion from net acid to net alkaline secretion by the rat stomach.
复制标题
胃内 pH 值调节大鼠胃从净酸分泌到净碱分泌的转化。
DOI：
10.1152/ajpgi.2001.281.4.g870
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Montrose,MH
中科院分区：
文献类型：
--
作者：
Coskun,T;Chu,S;Montrose,MH
Our previous report showed gastric mucosal surface pH was determined by alkali secretion at intragastric luminal pH 3 but by acid secretion at intragastric pH 5. Here, we question whether regulation of mucosal surface pH is due to the effect of luminal pH on net acid/base secretions of the whole stomach. Anesthetized rats with a gastric cannula were used, the stomach lumen was perfused with weakly buffered saline, and gastric secretion was detected in the gastric effluent with1) a flow-through pH electrode and2) a fluorescent pH-sensitive dye (Cl-NERF). During pH 5 luminal perfusion, both pH sensors reported the gastric effluent was acidic (pH 4.79). After perfusion was stopped transiently (stop-flow), net acid accumulation was observed in the effluent when perfusion was restarted (peak change to pH 4.1–4.3). During pH 3 luminal perfusion, both pH sensors reported gastric effluent was close to perfusate pH (3.0–3.1), but net alkali accumulation was detected at both pH sensors after stop-flow (peak pH 3.3). Buffering capacity of gastric effluents was used to calculate net acid/alkaline secretions. Omeprazole blocked acid secretion during pH 5 perfusion and amplified net alkali secretion during pH 3 perfusion. Pentagastrin elicited net acid secretion under both luminal pH conditions, an effect antagonized by somatostatin. We conclude that in the basal condition, the rat stomach was acid secretory at luminal pH 5 but alkaline secretory at luminal pH 3.
