热休克蛋白70对大鼠离体心脏细胞凋亡的影响

目的 观察热休克蛋白70(HSP70)对离体大鼠供心心肌细胞凋亡相关蛋白bcl-2、bax表达的影响.方法 Wistar大鼠18只,分为2组:对照组(C,n=9),腹腔注射生理盐水0.5 ml,24 h后取离体心脏灌注HTK心脏保护液,4 ℃保存3 h后建立Langendorff离体心脏灌注模型,灌注KH液2 h;实验组(E,n=9)腹腔注射重酒石酸去甲肾上腺素(溶于生理盐水中)3.1 μmol/kg(0.53 mg/kg),腹腔注射24 h后取离体心脏,处理方法旧C组.运用免疫组织化学SP法测定心肌HSP70含量、bcl-2、bax蛋白的含量并做统计学处理比较.结果 HSPT0含量E组(17.78±1.82)较C组(5.22±1.05)明显增高(P＜0.01),bel-2的表达E组(41.88±5.09)较C组(31.36±3.27)明显增多(P＜0.01),bax的表达E组(22.61±3.49)较C组(40.52±4.17)明显减少(P＜0.01),bel-2/bax比值E组(1.86±0.11)较C组(0.77±0.01)明显增高(P＜0.05).结论 心肌HSP70高表达能促进心肌抗凋亡蛋白bcl-2的表达,减少促凋亡蛋白bax表达,增加bel-2/bax比率,抑制心肌细胞凋亡.

The effects of heat shock protein 70 on myocardial cell apoptosis in isolated rat hearts

Objecgive To investigate the effects of heat shock protein 70(Hsfr70)on myocardial cell apoptosis in isolated rat hearts.Methotis Eighteen Wistar rats were randomly divided into 2 groups.In control group(C,n=9),0.5 ml normal saline was iniected intraperitoneally,and 24 h later isolated hearts were stored in 4℃ for 3 h with Histidine-tryptophan-ketoglutarate(HTK)solutions,and then perfusod for 2 h by Langendorff nlodel with Krebs-Henseleit(K-H)solutions.In experimental group(E,n=9),noradrenaline bitartrate(3.1 ixmol/kg,0.53 ms/kg)was injected intraperitoneally,and 24 h later isolated hearts were stored in 4 ℃ for 3 h with HTK.and then perfused for 2 h with Krebs-Henseleit(KH)solutions by Langendorff nlodel.HSP70 content,myocardial cell apoptosis.the expression of bcl-2 protein and bax protein were detected.Results HSP70 and bcl-2 contents in E group(17.78±1.82.41.88±5.09)were higher than those in C group(5.22±1.05.31.36±3.27)(P＜0.01).The expression level of bax protein in E group(22.61±3.49)was lower than in C group(40.52±4.17).Conclusion HSP70 cab affect the expression of myocardial bel-2 and bax proteins.and inhibit myocardial cell apoptosis.