心肌梗死后延迟骨髓细胞移植对大鼠心肌细胞bcl-2/baxmRNA及蛋白表达的影响  

Effects of delayed transplantation of bone marrow cells on the expressions of bcl-2/bax mRNA and proteins in myocardial cell in rat

作　　者：马东星[1] 刘惠亮[1] 张永珍[2] 赵蕊[3] 毛节明[2] 周春燕[4] 

机构地区：[1]武警总医院心内科,北京100039 [2]北京大学第三医院心内科 [3]北京大学第三医院病理科 [4]基础医学院生化与分子生物学系北京大学干细胞研究中心

出　　处：《解放军医学杂志》2005年第8期723-725,共3页Medical Journal of Chinese People's Liberation Army

基　　金：国家863重点项目(编号2001AA2160313);北京市科委重大项目(编号H020220010490);教育部"211工程"重点学科建设项目;北京大学985项目;武警总部重点科研项目(编号2002207)资助课题

摘　　要：目的观察心肌梗死(MI)后恢复期延迟的骨髓单个核细胞(BM-MNCs)移植对心肌细胞bcl-2/baxmRNA及蛋白表达的调节作用,并探讨影响凋亡的可能机制。方法通过结扎大鼠心脏左冠状动脉前降支制成MI模型。2周后第2次开胸,移植组在心外膜下梗死区及周边区多点注射BM-MNCs混悬液200μl(5×106个细胞),对照组予等体积PBS液。TUNEL法检测心肌细胞凋亡,免疫组化法检测Bcl-2、Bax蛋白在心肌细胞中的表达水平,原位杂交法检测bcl-2、baxmRNA表达变化。结果TUNEL结果显示心肌细胞凋亡指数在移植组明显低于对照组(4周:0·095±0·017vs0·173±0·018,P<0·05;8周:0·0926±0·014vs0·182±0·015,P<0·05)。免疫组化结果表明,移植组Bcl-2蛋白表达高于对照组(4周:12·66±3·37vs5·68±2·53,P<0·05;8周:13·08±3·09vs5·02±1·91,P<0·05),Bax蛋白表达则低于对照组(4周:11·48±3·13vs20·12±3·91,P<0·05;8周:9·98±3·03vs22·74±3·12,P<0·05)。第4、8周(治疗后第2、6周),移植组baxmRNA积分光密度和阳性面积较第2周降低,并低于对照组(P<0·05)。结论延迟至心肌梗死后2周行骨髓单个核细胞移植可抑制心肌细胞凋亡,其机制可能与对bcl-2、bax表达的调节有关。Objective To evaluate the effects of delayed transplantation of bone marrow mononuclear cells （BM-MNCs） after myocardial infarction （MI） on the expressions of bcl-2/bax mRNA and proteins in myocardial cells, and to explore the possible mechanism of cardiomyocyte apoptosis. Methods The MI rat model was reproduced by ligating the left anterior descending coronary artery. Two weeks later 5×10^6 of BM-MNCs were injected into the infarct zone and the peri-infarct zone （BMT group）. TUNEL was used to determine the cardiomyocyte apoptosis, immunohistochemical method was employed to detect the expressions of bcl-2 and bax protein, and the technique of hybridization in situ was applied to assess the changes in of bcl-2/bax mP, NA expression. Results TUNEL results indicated that apoptosis index of BMT group was lowered significantly compared with the control group （4 weeks： 0. 095 ±0. 017 vs 0. 173 ±0. 018; 8 weeks： 0. 0916±0. 014vs 0. 182±0. 015, P〈0. 05）. Immunohistochemistry and hybridization in situ revealed that bcl-2 expression was upregulated in the BMT group compared with the control group （P〈0. 05）, meanwhile bax expression was reduced in the BMT group（P〈0. 05）. Conclusion BMT could inhibit cardiomyocytes apoptosis by regulating the expressions of bcl-2 and hax and thus improved cardiac function.

关 键 词：细胞移植 心肌梗死 细胞凋亡 

分 类 号：R542.22[医药卫生—心血管疾病]