摘要
目的 探讨p5 3和Bcl- 2蛋白在实验性急性心肌梗死 (AMI)心肌细胞凋亡中的作用。方法 用TUNEL法检测 48只兔AMI模型梗死区的心肌细胞凋亡 ,用免疫组化法检测p5 3和Bcl- 2蛋白在心肌细胞中的表达水平 ,并探讨它们之间的相互关系。结果 TUNEL法发现兔梗死区心肌细胞凋亡千分率在冠脉结扎前 (0h)和结扎后 1、2、3、4、6、8、12h的改变如下 :0h组 (31 0 0± 14 0 0‰ )和 12h组 (6 8 0 0± 31 72‰ ) <1h组 (142 33± 5 3 5 2‰ ) <2h组 (370 83± 6 6 0 1‰ )和 8h组 (32 1 17± 86 43‰ ) <3h组 (5 86 83± 5 5 0 2‰ ) <4h组 (836 17± 43 73‰ ) (P均 <0 0 5 ) ,即急性心梗心肌细胞凋亡数在冠脉结扎后 1h时开始逐渐增多 ,到 4h时达高峰 ,其后逐渐下降 ,到 12h时已逐渐降至正常 ;阳性表达的p5 3蛋白积聚于胞核内 ,阳性心肌细胞千分率在冠脉未结扎 (0h)组 (4 5± 4 14 )和结扎后 1h组 (37 33± 35 43‰ )、2h组 (71 33± 5 4 93‰ )、8h组 (76 6 0±45 31‰ )、12h组 (6 5 0± 4 32‰ ) (P均 <0 0 5 ) ,而其它各组之间相互比较则无统计学上的差异 (P均 >0 0 5 ) ;阳性的Bcl- 2蛋白积聚于胞浆中 ,阳性心肌细胞千分率在冠脉结扎后 3h组 (41 0 0± 2 1 6 0‰ )、4h组 (6 83± 5 34‰ )和
Objective To investigate the expression and significance of p53 and Bcl-2 protein in myocyte apoptosis in infarct area in AMI rabbit model.Methods TUNEL was applied to monitor the myocyte apoptosis. p53 and Bcl-2 protein expression were assessed by immunohistochemistry, and to investigate their relationships.Results In the AMI rabbit model, TUNEL method showed that the permillage of apoptotic myocytes in infarct area at 1 h, 2 h, 3 h, 4 h, 6 h, 8 h, 12 h after coronary artery occlusion and before coronary artery occlusion (0 h) were:0 h group (31.00±14.00‰) and 12 h group (68.00±31.72‰)<1 h group (142.33±53.52‰)<2 h group (370.83±66.01‰)and 8 h group (321.17±86.43‰)<3 h group (586.83±55.02‰)<4 h group (836.17±43.73‰)( P <0 05). The number of apoptotic myocytes was increased gradually after 1 h occlusion of coronary artery, reaching to the top at the 4th hour, then decreased slowly to normal at the 12th hour. Expression of p53 protein accumulated in nuclear of cells, the permillage of possitive myocytes at 3 h (175.67±76.38‰), 4 h(240.00±106.05‰) and 6 h (164.00±81.81‰) in occlusion group was significantly higher than that in 0 h group (4.5±4.14‰), 1 h group (37.33±35.43‰),2 h group (71.33±54.93‰), 8 h group (76.60±45.31‰),12 h group (6.50±4.32‰) after coronary artery occlusion ( P <0 05),whereas the differences among other groups was not significant( P >0 05).Bcl-2 protein expression accumulated in plasma of myocyted. The permillage of positive myocytes at 3 h group (41.00±21.60‰), 4 h group (6.83±5.34‰) and 6 h group (32.50±19.13‰)<0 h group (169.50±60.68‰), 2 h group (107.00±36.30‰), and 8 h group (175.67±69.25‰)<1 h group (207.50±49.75‰) and 12 h group (248.83±96.00‰) after coronary artery occlusion ( P <0 05).Morevere, the amount of most apoptosis in infarct area was positively correlated to p53 protein expression( r =0.9873, P <0 001),and was negatively correlated to Bcl-2 protein expression( r =-0.9384, P <0 001).In addition, the significantly negative correlation was found between expression of p53 protein and Bcl-2 protein in myocytes of infarct area ( r =0.9269, P <0 001).Conclusions The marked characteristics of apoptosis in myocytes of infarct area induced by AMI were found, which were regulated by p53 protein up-regulate and Bcl-2 protein down-regulate. [
出处
《中国急救医学》
CSCD
北大核心
2000年第8期443-447,共5页
Chinese Journal of Critical Care Medicine
基金
卫生部基金!资助项目 (1 996 - 1 - 1 1 6)
