脉络宁对新生大鼠缺氧缺血性脑损伤后nNOS和c-Fos表达的影响

目的:检测新生大鼠缺血缺氧后神经元型一氧化氮合酶(nNOS)和c-Fos免疫活性表达改变及脉络宁对其的影响。方法:结扎7d龄大鼠右侧颈总动脉1h,然后暴露在8%氧和92%氮的混合气体中2h,建立缺氧缺血脑损伤模型。用免疫组织化学方法检测并比较缺血缺氧后和脉络宁处理后c-Fos和nNOS的免疫活性。结果:缺血缺氧6h后c-Fos表达达高峰;与缺氧缺血组相比,脉络宁处理组c-Fos阳性神经元数量增加,表达c-Fos的时间延长;与假手术组相比,缺氧缺血组nNOS表达水平增高,脉络宁处理组则下降。结论:脉络宁可抑制nNOS表达,增强c-Fos表达,可能对缺血缺氧性脑损伤有保护作用。

The Effects of Mailuoning on Expressions of Neuronal Nitric Oxide Synthase and c-Fos After Hypoxic-Ischemic Brain Damage in Neonatal Rats

Objective: To detect the changes in the expressions of neuronal nitric oxide synthase (nNOS) and c-Fos immunoactivity, as well as the effect of Mailuoning after hypoxic-ischemic brain damage in neonatal rats. Methods: The right common carotids of the neonatal SD rats (7 days) were ligated for one hour, and then they were exposed to 8% oxygen and 92% nitrogen gas mixture for two hours establishing the model of hypoxic-ischemic brain damage. Immunoactivity of c-Fos and nNOS were measured by immunohistochemistry after hypoxic ischemia and the treatment of mailuoning. Results: The expression of c-Fos reached to peak after six-hour hypoxia and ischemia. As compared with the hypoxic-ischemic group, the numbers of c-Fos positive neurons increased and the expressive time c-Fos prolonged in mailuoning treated group. As compared with the false-operation group, the levels of nNOS expression in the hypoxic-ischemic group increased, while the levels of nNOS expression decreased in the mailuoning treated group. Conclusions: Mailuoning inhibits the expression of nNOS and increases the expression of c-Fos. It may have the protective effect on hypoxic-ischemic brain damage.