NOS在脑缺血再灌注大鼠肺肝肾组织中的作用

Changes of Nitric Oxide Synthase in Lung,Liver and Kidney after Cerebral Ischemia Reperfusion in Rats

目的:检测脑缺血再灌注大鼠肺、肝、肾组织中一氧化氮合酶(NOS)的活性及作用。方法:按改良的Pulsinelli方法建立大鼠脑缺血再灌注模型,分别测定假手术组(S组)、缺血再灌注组(I组)2、6、12、24及48 h时肺、肝、肾组织中NOS活性。结果:与S组比较,I组总NOS活性在2、12及24 h时均升高,以12 h时最显著(P<0.01),其中2 h时以结构型NOS(cNOS)上升为主(P<0.05),12 h时以诱导型NOS(iNOS)上升为主(P<0.01);在24 h时iNOS仍高(P<0.05),48 h时基本接近S组水平。结论:不同类型NOS在脑缺血再灌注不同阶段肺、肝、肾组织中活性不同,早期(<6 h),cNOS活性升高,对器官损害具有保护作用;后期(12-24h),iNOS活性显著上升,介导了迟发性组织损伤。

Objective：To explore the effects of nitric oxide synthase （NOS） on lung, liver and kidney injures after cerebral ischemia reperfusion in rats. Methods.. The rats were randomly divided into two groups： sham operation group （group S）, group of ischemia 20 min plus reperfusion 2, 6, 12, 24 and 48 h （I/R group）. The cerebral ischemia reperfu sion models were established by modified Pulsinelli＇s. The activities of NOS in lung, liver and kidney were measured in all rats. Results：Compared with group S, the activities of total NOS were increased at 2, 12 h and 24 h in I/R group, and the peak occurred at 12 h （P〈0.01）. The activities of iNOS were increased significantly at 2 h （P〈0.05）, while the ac- tivities 6f iNOS were increased dramatically at 12 h （P〈0.01）. They were still at a high level at 24 h （P〈0.05） and re covered to the basic level at 48 h. Conclusion： The various types NOS play different roles in pulmonary, liver and kidney injures induced by cerebral ischemia-reperfusion in different phases in rats. In the earlier stage （〈6 h）, the activities of cNOS are increased significantly and may be useful to protect the lung, liver and kidney from injury; In the late stage （12 h-24 h）, the activities of iNOS are increased dramatically, which may mediate the delayed damages to tissues.