神经元型一氧化氮合酶在血管性痴呆大鼠海马中的表达

目的 探讨神经元型一氧化氮合酶(nNOS)在血管性痴呆(VD)大鼠海马中的表达。方法 将60只大鼠随机分为：对照组、VD12h组、VD1d组、VD3d组、VD7d组。采用反复夹闭双侧颈总动脉方法建立VD大鼠模型，用HE染色观察各组大鼠海马CA1区神经元的数目；应用免疫组化染色和Western印迹方法检测nNOS在大鼠海马中的表达。结果 VD12h组、VD1d组、VD3d组、VD7d组大鼠海马CA1区神经元数均明显下降。nNOS在对照组大鼠海马CA1区中弱表达．在VD12h组表达增强．VD1d组进一步增强，VD3d和7d组表达逐渐减弱。结论 nNOS可能参与缺血早期海马神经元的损害，是VD的发病机制之一。

Expression of nNOS in the hippocampus in vascular dementia rats

Objective To explore the expression of neuronal nitric oxide synthase (nNOS) in the hippocampus in vascular dementia rats.Methods 60 rats were randomly divided into five groups: control group, model 12 h group,model 1 d group, model 3 d group and model 7 d group.An animal model of vascular dementia (VD) was established through repeated cerebral ischemia-reperfusion in rats with repeated bilateral common carotid arteries occlusion. The number of neurons in CA 1 area of hippocampus in every group was observed using HE staining. The expression of nNOS in the hippocampus in VD rats was detected by immunohistochemical staining and western blot method.Results The number of neurons in CA 1 area of hippocampus decreased significantly in 12 h, 1 d, 3 d and 7 d group. The expression of nNOS in CA 1 area of hippocampus was weak in control group and up-regulated in 12 h group and increased further in 1 d group. However, its expression decreased gradually in 3 d and 7 d group.Conclusion nNOS may be related to the injury of hippocampus at early phase in VD rats. It might be regarded as one of mechanisms to cause VD.