L-精氨酸对应激状态下大鼠胃黏膜损伤及壁细胞泌酸的影响

 目的探讨L-精氨酸(L-Arg)对应激状态下大鼠胃黏膜损伤及壁细胞泌酸功能的影响。方法 采用水浸-束缚(WRS)方 法建立大鼠应激性溃疡(SU)模型,将动物随机分为正常对照组(NC)、WRS组、WRS+L-Arg组和WRS+L-Arg+L-NAME组,检 测胃黏膜溃疡指数(UI)、胃黏膜一氧化氮(NO)含量、胃液pH值和壁细胞H⁺,K⁺-ATP酶活性,光镜下观察胃黏膜组织学改变。 结果 与WRS组相比,WRS+L-Arg组胃液pH值升高,壁细胞H⁺,K⁺-ATP酶活性下降,胃黏膜NO含量增加,UI明显下降,光 镜下胃黏膜的损伤轻于WRS组;与WRS+L-Arg(300 mg·kg^-1)组相比,WRS+L-Arg+L-NAME组pH值下降,H⁺,K⁺-ATP酶活 性升高,胃黏膜NO含量下降,UI升高,胃黏膜损伤加重。结论 L-Arg对应激状态下大鼠胃黏膜具有保护作用,其机制与NO 抑制壁细胞泌酸有关。

Effects of L-arginine on gastric mucosal lesion and acid secretion function of parietal cells in rats under stress

OBJECTIVE To demonstrate the effects of L-arginine on gastric mucosal lesion and the acid secretion function of parietal cells in rats under stress.METHODS Water immersion-restraint stress (WRS) model was performed and SD rats were randomly divided into normal control group, WSR group, WRS+L-arginine groups and WRS +L-arginine + L-NAME group. The gastric mucosal ulcer index (UI), NO contents in gastric mucosa, pH value of gastric juice and H⁺ ,K⁺ -ATPase activity of parietal cells were measured. The structural change of gastric mucosa was observed under light microscope. RESULTS Compared with WRS group, the pH value of gastric juice increased and H⁺, K⁺-ATPase activity of parietal cells decreased obviously, the NO contents in gastric mucosa increased and the UI decreased significantly, and the damage of gastric mucosa was improved in WRS + L-arginine groups. Compared with WRS + L-arginine (300 mg·kg^-1) group, the pH value decreased and H⁺, K⁺ -ATPase activity increased obviously, the NO contents in gastric mucosa decreased and the UI increased significantly, and the damage of gastric mucosa was aggravated in WRS + L-arginine + L-NAME group. CONCLUSION L-arginine plays an important mle in protecting gastric mucosa from injuried rats prepared by WRS. The mechanism may be associated with the endogenous nitric oxide inhibiting the acid secretion function of parietal cells.