束缚应激对大鼠血小板-氧化氮释放的影响

目的 观察急性应激对大鼠血小板一氧化氮(NO)释放的影响及其机制.方法 大鼠浸水-束缚应激(WRS)2、4和8 h,以胃溃疡指数(UI)作为应激损伤的标识,采用Greiss法测定血小板孵育液中亚硝酸盐(NO2-)含量;同位素法测其一氧化氮合酶(NOS)活性和L精氨酸(L-Arg)转运量.结果 WRS 2 h血小板L-Arg转运量、NOS活性和孵育液NO2-含量较对照组显著增加,但随应激时间延长,其呈下降趋势,应激8 h时均显著低于对照组,胃溃疡逐渐加重.结论 WRS应激早期阶段可上调血小板L-Arg/NO通路,促进血小板NO生成;长时间应激下调L-Arg/NO通路,减少NO释放.

Effect of water-immersion restraint stress on nitric oxide production pathway in rat platelets

Objective To investigate the effect of water-immersion restraint stress(WRS) on nitric oxide(NO) production and its mechanism in rat platelets.Methods Male SD rats underwent WIR stress for 2,4 and 8 hours.Ulcer index(UI) of stomach was chedsed by Guth method,nitrite production was measured by Greiss assay,nitric oxide synthase(NOS) activities and L-arginine transport rate were determined by isotope tracer method.ResultsAfter 2 h WRS,the NO production,the NOS activity and L-arginine transport rate in rat platelets obviously increased and then gradually decreased.After 8 h of WRS,these parameters were decreased as compared with the control group.The gastric ulcer appeared and got more serious after 4 h WIR stress.Conclusion Short-term WRS up-regulates L-arginine /NO pathway and increases nitric oxide production in the platelets but long-term WIR stress has the reversed effect.