芳香开窍法对全脑缺血再灌注大鼠脑组织NO含量及NO合酶表达的影响

目的]研究以麝香、冰片为代表的芳香开窍中药对大鼠脑组织一氧化氮(NO)含量及一氧化氮合酶内皮细胞型(eNOS)、一氧化氮合酶诱导型(iNOS)表达量的影响。方法]Pulsinelli的4VO法建立大鼠全脑缺血再灌注模型,采用硝酸还原酶法测定NO及免疫组织化学染色技术观察脑微血管eNOS、iNOS及神经元iNOS表达,并进行半定量分析。结果]芳香开窍中药和尼莫通能减少缺血再灌注大鼠脑组织中NO的含量,并接近于正常,与模型组比较P<0.01,与假手术组比较P>0.05。对NOS的两个亚型iNOS和eNOS分析提示芳香开窍药能提高脑微血管eNOS的表达,降低神经元及脑微血管iNOS表达(与模型组比P<0.01)。结论]芳香开窍药有促进内皮细胞产生合成NO,同时也能降低神经元及微血管iNOS表达,从而减少总NO的生成量,降低缺血引起的NO毒性作用,对脑组织具有一定的保护作用。

Effect of Aromatic Herbs for Resuscitation on NO Content and Expression of NOS in Brain Tissue of Rats with Cerebral schemia and Reperfusion Injury

Objective] To investigate the effect of aromatic herbs for resuscitation such as Moschus and Borneol on nitric oxide (NO) content and expression of endothelial NO synthetase (eNOS) and inducible NO synthetase (iNOS) in brain tissue of rats with cerebral ischemia and reperfusion injury. Methods] Forty rats were allocated to 4 groups: mimic operation group (Group A), model group (Group B), herbs treatment group (Group C) and nimodipine treatment group (Group D). Rat model of cerebral ischemia and reperfusion injury was established by Pulsinelli 4VO method. NO content in brain tissue was determined by nitrate reductase method. Expression of eNOS and iNOS in micrangium and iNOS in neurons was measured by semi-quantitative analysis. Results] NO content was decreased and approached normal level in Group C and Group D (P < 0.01 as compared with Group B and P > 0.05 as compared with Group A). Aromatic herbs with action of inducing resuscitation increased the expression of eNOS in micrangium and decreased the expression of iNOS in micrangium and neurons, the differences being significant as compared with those in Group B ( P < 0.01). Conclusion] Resuscitation-inducing aromatic herbs promote the formation of NO in endothelial cells and reduce the expression of iNOS in micrangium and neurons and then decrease the total amount of NO content. Resuscitation-inducing aromatic herbs prevent brain tissue from ischemic damage by lowering the toxicity of NO.