大鼠缺血再灌注后NOS表达与小动脉损伤关系的实验研究

Study on the relation between morphological changes of small artery and expression of NOS in rats after ischemia-reperfusion

目的:探讨大鼠缺血再灌注(IR)后一氧化氮合酶(NOS)在不同时点表达与小动脉形态学改变的关系及临床意义。方法:将大鼠分为正常对照组;缺血45min组;缺血再灌注1h组、3h组、6h组、12h组、24h组。建立失血性休克动物模型并给与治疗后用光镜和透射电镜观察小动脉内皮和平滑肌细胞的形态学改变,同时用免疫组化显示NOS在小动脉内皮和平滑肌细胞表达的阳性细胞数。结果:1光镜和电镜下缺血45min组小动脉轻微损伤。再灌注后损伤加重,以3h组损伤最显著。脑的小动脉与其它组织相比较,在缺血及再灌后不同时点的损伤较轻,再灌注6h后逐渐恢复。2正常对照组NOS不表达,缺血45min后NOS表达量首先增加,再灌后1h组达到高峰,3h组表达减弱。缺血45min组、IR3h组、IR6h组、IR12h组、IR24h组与正常对照组比较,差异均有统计学意义(P<0.05)。结论:1大鼠缺血再灌注可引起小动脉内皮和平滑肌损伤。2NOS对小动脉内皮和平滑肌缺血再灌注损伤可能具有保护作用。

Objective：To study the relation between the morphological changes of small artery and expression of NOS in rats after the ischemia-resuscitation.Methods：Specimen of tissues were taken in the ischemia 45 minutes and reperfusion for 1、3、6、12、24 hours.The morphological changes of small artery was observed by light microscope and electron microscope.The expression of NOS in the small artery was observed by the immunohistochemistry technique.Results：①Light microscope and electron microscope：The injury degree of small artery in 45 min ischemia group was slight,the injury degree of reperfusion was more severe than that in ischemia group.The most severe cellular damage was found in 3 hour after reperfusion.Compared with the other tissues,the injury degree of small artery in brain was more slightly.②The expression of NOS was not increased in the normal group,but the expression of NOS in the ischemia and reperfusion groups were changed successively.The expression of NOS was increased after ischemia 45 min,it peaked after reperfusion for 1 hour,and began to decrease gradually after reperfusion for 3 hours.Compared with the control group（P0.05）.Conclusion：The ischemia-resuscitation can induce the morphological changes of small artery and the ischemia-reperfusion damage of small artery.NOS are play an important role in ischemia-reperfusion damage of small artery.The ischemia/reperfusion damage of small artery is likely protected by NOS.