缺血后处理对肺缺血/再灌注损伤的保护作用及其机制  

Ischemic postconditioning attenuates pneumocyte apoptosis after lung ischemia/reperfusion injury via inactivation of p38 MAPK

作　　者：陈海娥[1] 马迎春[1] 何金波[1] 黄林静[1] 陈丹[1] 应磊[1] 王万铁[1] 

机构地区：[1]温州医科大学缺血-再灌注损伤研究所病理生理学教研室,浙江温州325035

出　　处：《中国应用生理学杂志》2014年第3期251-256,共6页Chinese Journal of Applied Physiology

基　　金：温州市高层次人才创新技术重点资助项目(2011-05);浙江省中医药重点学科建设计划(2012-XK-A28)

摘　　要：目的:探讨缺血后处理(IPO)是否通过抑制P38丝裂原活化蛋白激酶(P38MAPK)活化来减轻再灌注损伤肺细胞的凋亡。方法:雄性SD大鼠40只,随机分成5组(n=8),即对照组(C组)、肺缺血/再灌注组(I/R组)、肺缺血/再灌注+缺血后处理组(IPO组)、缺血后处理+溶剂对照组(D组)、缺血后处理+SB203580组(SB组)。各组分别于再灌注2 h留取左肺组织,检测肺组织湿/干重比(W/D)和总肺含水量(TLW);光镜观察肺组织形态学结构改变并进行肺组织损伤定量评估(IQA);原位末端标记法(TUNEL)检测肺细胞凋亡情况并计算凋亡指数(AI);RT-PCR和免疫组化法测定Bax、Bcl-2基因和蛋白的表达。结果:与C组相比,I/R组W/D、TLW、IQA和AI均显著升高(P<0.05,P<0.01),肺组织结构发生明显损伤;Bcl-2、Bcl-2/Bax基因及蛋白表达明显降低,Bax基因及蛋白表达明显升高(P<0.05,P<0.01);IPO组、D组、SB组与I/R组相比,W/D、TLW、IQA和AI均显著降低(P<0.05,P<0.01),肺组织结构损伤情况有所改善;Bcl-2、Bcl-2/Bax基因及蛋白表达明显升高,Bax基因及蛋白表达明显降低(P<0.05,P<0.01);D组与IPO组比较各项指标均无明显差异(均P>0.05);SB组与IPO组相比,肺组织W/D、TLW、IQA和AI均显著降低(P<0.05,P<0.01),肺组织结构未见明显损伤;Bcl-2、Bcl-2/Bax基因及蛋白表达明显升高,Bax基因及蛋白表达明显降低(P<0.05,P<0.01)。结论:I/R通过激活P38MAPK导致大鼠肺泡结构严重破坏,肺内细胞大量凋亡;IPO可能是通过抑制P38MAPK通路的激活而减轻I/R损伤。Objective： To investigate the role of p38 MAPK on ischemic postconditioning （lPO） attenuating pneumocyte apoptosis after lung ischemia/reperfusion injury（LIRI）. Methods： Forty adult male SD rats were randomly divided into 5 groups based upon the intervention （n=8）： control group （C）, LIR group （I/R）, LIR＋ IPO group （IPO）, IPO＋ solution control group（D）, IPO＋ SB203580 group（SB）. Left lung tissue was isolated after the 2 hours of reperfusion, the ratio of wet lung weight to dry lung weight（W/D）, and total lung water content （TLW） were measured. The histological structure of the left lung was observed under light and electron transmission microscopes, and scored by alveolar damage index of quantitative assessment （IQA）. Apoptosis index（AI） of lung tissue was determined by terminal deoxynuleotidyl transferase mediated dUTP nick end and labeling （TUNEL） method. The mRNA expression and protein levels of and Bax were measured by RT-PCR and quantitative immunohistochemistry （IHC）. Results： Compared with C group, W/D,TLW,IQA.AI and the expression of Bax of I/R were significantly increased, the expression of Bcl-2 and Bcl-2/Bax were significantly decreased （ P 〈 0.05, P 〈 0.01 ）, and was obviously morphological abnormality in lung tissue. Compared with I/R group, all the indexes of IPO except for the expression of Bcl-2 and Bcl-2/Bax were obviously reduced, the expression of Bcl-2 and Bcl-2/Bax were increased（ P 〈 0.05, P 〈 0.01 ）. All the indexes between D and IPO were little or not significant（ P 〉 0.05）. The expression of Bcl-2 and Bcl-2/Bax of SB were significantly increased and other indexes were reduced than those of IPO（ P 〈 0.05, P 〈 0.01 ）. Conclusion： IPO may attenuate pneumoeyte apoptosis in LIRI by inactivation of p38 MAPK, up-regulating expression of Bcl-2/Bax ratio.

关 键 词：缺血 再灌注 缺血后处理 细胞凋亡 P38MAPK SB203580 Bcl-2 BAX 

分 类 号：R363[医药卫生—病理学]