银杏叶提取物联合盐酸文拉法辛对抑郁大鼠海马nNOS蛋白表达及NO水平的影响

目的 :探讨抑郁症脑损伤的机制 ,研究银杏叶提取物 (EGb)及合成抗抑郁药盐酸文拉法辛(Venlafaxine)对抑郁大鼠的抗脑损伤及神经元保护作用。方法 :慢性应激建立大鼠抑郁模型。将 84只雄性大鼠分为正常对照组、抑郁模型组和不同治疗组。快速断头法处死 ,取海马后一侧进行免疫组化反应 ,观察海马CA3区nNOS蛋白的表达 ;另一侧检测NO含量 ;同时测定血清中NO含量。结果 :抑郁模型组海马nNOS表达增加 ,海马及血清中NO含量增加 ,P <0 0 1;联合用药组海马nNOS表达下降 ,海马及血清中NO含量减少 ,P <0 0 1。结论 :慢性应激增加海马nNOS表达 ;EGb有减轻神经元损伤 ,保护神经元的作用 ,其与Venlafaxine合用可能会达到对抑郁进行多靶点、多层次的治疗 ,弥补单一用药的不足。

The Effects of EGb and Venlafaxine on the Expression of nNOS and NO level in Rats of Depression Model

Objective: To observe the changes of hippocampus in the rats of depression model and study the protective effects of EGb (extracts of gingkobiloba) and Venlafaxine on brain injury. Methods: Rats were divided into 6 groups. Groups A served as normal control. Group B?C?D?E?F received 21 days chronic stress. Group C?D?E?F were fed with normal food, EGb, Venlafaxine and EGb+Venlafaxine respectively for 28 days after enduring 21 days chronic stress. Every rat had been observed open-field behavior before decapitated.One side of the hippocampus were measured the expression of nNOS by immunohistochemistry method, the other side hippocampus and the serum were measured the concentrations of NO.Results:The expression of protein nNOS in hippocampus of group B was increased compared with group A (P<0.01).The expression of protein nNOS was significantly different between group C and group D?F respectively(P<0.01). The concentrations of NO in serum and hippocampus were significant increased in group B (P<0.05). Compared with NO of group C, NO in hippocampus of group D 2?F and in serum of group F were decreased significantly (P<0.05). Conclusion: Chronic and comprehensive stress decreased the exploring behaviours, inhibited grooming behaviours and increased defecation of rats. Chronic and comprehensive stress increased the expression of nNOS in hippocampus and showed a descent tendency in a time-dependent way. EGb has the effects of relieve the injury of neurons, enhances the plasticity of CNS and has antidepressant-like properties.