大鼠肢体缺血再灌注后肺组织一氧化氮合酶的变化

Changes of nitric oxide synthase in lung of rats after ischemic reperfusion of hind limbs

目的 :研究正常大鼠肺组织内一氧化氮合酶 (NOS)的分布及肢体缺血再灌注 (LIR)后肺组织内NOS分布及活性的变化。方法 :用止血带复制肢体缺血再灌注模型 ,利用 β -NADPH -d组织化学方法、计算机图像分析系统及分光光度法 ,观察对照组大鼠肺内NOS的分布及LIR组肺内NOS分布及活性的变化。结果 :组织学上显示 ,对照组大鼠呼吸道包括支气管、细支气管、终末细支气管、肺泡管的上皮细胞和血管内皮细胞NOS表达均阳性 ,肺泡上皮细胞NOS表达阴性 ;LIR组上述肺组织阳性部位NOS表达增强 ,且出现血管平滑肌细胞、肺泡上皮细胞NOS表达阳性 ;生化测定结果显示 ,LIR组与对照组比较 ,NOS活性增强 ,NO2 -/NO3 -水平增多。结论 :一氧化氮不仅参与肺的生理过程 ,而且在LIR后急性肺损伤 (ALI)

AIM: To study the distribution of nitric oxide synthase (NOS) in normal lung of rats, and the changes in distribution and activity of NOS in lung of rats suffering from limb ischemia reperfusion (LIR). METHODS: Using tourniquet, the model rats undergoing ischemia reperfusion were made. Using β-ANDPH-d histochemical method, computer analysis of image and spectrophotography, the distribution of NOS in normal lungs of rats, and the changes in distributon and activity of NOS in lung of rats suffering from limb ischemia reperfusion (LIR) were observed. RESULTS: Histochemically, in normal rats, the NOS positive staining was found in epithelial cells of respiratory duct including bronchi, alveolar duct as well as in endothelium of pulmonary vessels, and the negative staining was found in pneumonocytes. In LIR rats, the above NOS staining were significantly stronger than that in normal one, and positive staining was also found in vascular smooth muscle and pneumonocytes. Biochemically, the results showed that the values of lung NOS, NO in LIR group increased significantly compared with the normal control. CONCLUSION: NO may play an important role not only in physiology of lung but also in pathophysiology of acute lung injury following LIR. [