L-NAME对大鼠局灶性脑缺血灌注损伤Fos蛋白表达的影响

The effects of L-NAME on Fos expression in the rat brain during reperfusion after focal cerebral ischemia

目的观察一氧化氮含量的变化对缺血再灌注损伤后Fos蛋白表达的影响。方法采用线拴法制作大鼠局灶性脑缺血再灌注损伤模型，利用NADPH组化和Fos蛋白免疫组化双标技术研究NOS抑制剂L－NAME对大鼠局灶性脑缺血再灌注损伤脑皮层Fos蛋白表达的影响。结果缺血60min再灌注3h后损伤侧脑组织皮质一氧化氮合酶阳性神经元较正常增多并深染，Fos蛋白表达增加，L－NAME（3mg／kg）治疗组脑皮质神经元Fos蛋白的表达量较对照组减少，L－NAME（10mg/kg）治疗组脑皮质神经元Fos蛋白的表达量较对照组明显减少，同时也可见给予L－NAME后脑组织皮质内NOS阳性神经元无论在数量上还是在细胞着色、胞体突起均明显减少。结论c－fos基因表达也可能部分参与了NO的致神经细胞损伤过程。

Objective: To investigate the effects of nitric oxide on Fos expression in the rat brain duringreperfusion after focal cerebral ischemia. Methods: Using double-labeled technique of NADPH-diaphoraseand Fos immuno-reactivity, We observed the changes of NADPH-diaphorase histochemistry and expressionof Fos protein in the neurones during reperfusion after being administered various dose of the competitivenitric oxide synthase (NOS) inhibitor, N-nitro-L-arginine methyl ester(L-NAME). Results: NOS positiveneurons and Fos expression were increased in the ipsilateral cortex at 3 hours after reperfusion,administeration of L-NAME (3mg/kg, 1Omg/kg i. p) reduced the expression of Fos protein in a dose-related way. Conclusion: These resultes indicated that there is a functional relationship between NOS andc-fos intracellular systems, which are supposed to be involved in the pathogenesis of neuronal injury aftercerebral ischemia and reperfusion.