摘要
目的:探讨肢体缺血再灌注(LIR)后肺的损伤性变化以及细胞凋亡在肺损伤发生中的作用;探讨一氧化氮(NO)对LIR后肺组织细胞凋亡的影响。方法:采用本室常规方法复制大鼠LIR模型,给予外源性一氧化氮合酶底物(L-Arg)和一氧化氮合酶抑制剂(L-NAME)处理,采用原位末端标记法(TUNEL)检测缺血4h再灌注4h时各组动物肺组织细胞凋亡情况;采用放免法检测凋亡相关细胞因子TNF-α在肺组织的表达,结合计算机分析系统对结果进行定量分析;采用免疫组织化学方法检测Bcl-2、Bax、caspase-3、TNF-α蛋白表达情况,结合自动图像分析系统对其结果进行定量分析;在光镜下观察肺组织的形态学改变。结果:大鼠LIR后4h,肺泡Ⅱ型上皮细胞、肺血管内皮细胞呈凋亡改变,肺组织TNF-α、caspase-3、Bax明显上调,Bcl-2表达下调。L-Arg处理组,凋亡细胞数明显减少,肺组织TNF-α、caspase-3、Bax的表达情况与IR组相比明显减弱,Bcl-2表达明显增强;L-NAME处理组动物肺组织TNF-α、caspase-3、Bax的表达情况与IR组相比明显增强,Bcl-2表达明显减弱。结论:细胞凋亡参与了大鼠LIR后急性肺损伤的发生,且与TNF-α有关;NO可通过减弱细胞凋亡相关因子TNF-α的表达,减轻LIR后肺组织的细胞凋亡。
AIM : To investigate the injury of lung and the role of cell apoptosis in the pathogenesis of acute lung injury following ischemia - repeffusion of hind limbs and the influence of nitric oxide (NO) to apoptosis. METHODS: Referring to our laboratory normal method, the model rats, which underwent 4 hours ischemia and 4 hours reperfusion of hind limbs were made. L - arginine ( L - Arg) and N - nitro - L - arginine methyl ester ( L - NAME) was adminis- trated respectively to these rats before the experiment. Apoptosis was detected by TdT - mediated dUTP nick end labeling (TUNEL), respectively. The radioimmunoassay (RIA) was used to detect level in the expression of TNF-α. The immu-nohistochemistry (IHC) method was used to detect the level in the expression of Bcl - 2, Bax, caspase - 3 and TNF-α. The morphologic changes were observed under microscope, respectively. The results of the RIA and the IHC were analyzed quantitatively by relative computer analytical system. RESULTS: After rats's hind limbs suffered from ischemia - repeffu- sion, the apoptosis in alveolar epithelial cells and pulmonary vascular endothelial cells was found. The expression of TNF-α, caspase - 3 and Bax increased. Compared with IR rats, the expressions of TNF-α, caspase - 3 and Bax were not obvi- ous in the L - Arg administrated group, but the expression of Bcl - 2 was obvious in that group. Compared with IR rats, the expressions of TNF-α, caspase - 3 and Bax were obvious in the L - NAME administrated group, but the expression of Bcl - 2 was not obvious in that group even weaker than normal ones. CONCLUSION: Apoptosis participated in acute lung in- jury following ischemia - repeffusion of hind limbs. The excess expression of TNF-α related with apoptosis of alveolar epithelial cells and pulmonary vascular endothelial cells. NO may reduce the occurrence of apoptosis and other lung injury through down - regulating the level in the expression of TNF-α.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2007年第11期2214-2216,共3页
Chinese Journal of Pathophysiology
基金
河北省教委科研基金资助项目(No990117)
作者简介
通讯作者:张连元 Tel:0315-3725612;E-mail:Lianyuan-zhang@163.com