锌对急性缺氧小鼠大脑皮层NOS活力和nNOS蛋白表达的影响

EFFECT OF ZINC ON THE ACTIVITY OF NOS AND EXPRESSION OF nNOS IN CEREBRAL CORTEX OF ACUTE HYPOXIC MICE

目的观察锌对急性缺氧小鼠大脑皮层一氧化氮合酶 (NOS)和神经元型一氧化氮合酶 (nNOS)阳性神经元的变化 ,探讨锌抗脑缺氧的作用机制。方法制备小鼠急性缺氧模型 ,采用NADPH -d组织化学和nNOS免疫组织化学方法 ,研究给锌组和不给锌组急性缺氧小鼠大脑皮层NOS和nNOS阳性神经元数量的变化。结果给锌组比不给锌组小鼠的耐缺氧时间延长 33.0 6 %(P <0 .0 5 ) ,大脑皮层NOS和nNOS阳性神经元数量分别减少 18.0 3%和 2 1.6 3% ,(P <0 .0 5 )。结论急性缺氧时锌通过减少皮层NOS活力和nNOS水平而发挥其抗脑缺氧作用。

Objective To explore the effect of zinc on the activity of nitric oxide synthase (NOS) and the expression level of neuronal nitric oxide synthase(nNOS) in the cerebral cortex of acute hypoxic mice and the protective effects of zinc. Methods Acute hypoxic model in mice was made. NADPH-d histochemistry and nNOS immunohistochemistry were used to investigate the changes of positive neurons of NOS and nNOS in different groups. Results The time of tolerance to hypoxia increased 33.06% more (P<0.05) while the number of NOS positive neurons and nNOS positive neurons in cerebral cortex decreased 18.03% and 21.63%more respectively(P<0.05) in zinc supplementation group than in saline control group, Conclusion Zinc might play an important role in decreasing the activity of NOS and the level of nNOS in cerebral cortex to protect the brain against hypoxic damage.