外源性热休克蛋白70基因对心肌细胞损伤的保护作用

目的：探讨热休克蛋白70（HSP70）基因转染对心肌细胞急性实验性缺氧／复氧损伤的保护作用及其机制。方法：进行大鼠乳鼠原代心肌细胞培养，随机分为4组，对照组、缺氧／复氧（A／R）组、热休克处理后缺氧／复氧（A／R＋HS）组和pCDNAHSP70质粒转导后缺氧／复氧（A／R＋pCDNA HSP70）组。用脂质体包裹pCDNAHSP70质粒，并转导入心肌细胞内。反转录-聚合酶链反应（RT-PCR）检测HSP70mRNA表达，Westernblot检测HSP70蛋白表达。以心肌细胞存活率（MTT法）、培养液中乳酸脱氢酶（I．DH）活性、心肌细胞超微结构改变（透射电镜）及Ca^2＋负荷来检测心肌细胞损伤程度。结果：与A／R组相比，A／R＋HS组和A／R’pCDNAHSP7。组细胞存活率显著提高；LDH活性明显降低；细胞超微结构明显改善；心肌细胞Ca^2＋负荷明显减轻。A／R组HSP70mRNA和蛋白含量均较A／R＋HS组和A／R＋pCDNAHSP70组显著减低（P〈0．01），而A／R＋pCDNA HSP70组的含量与A／R＋HS组相比显著增多（P〈0．01）。结论：通过基因转染使HSP70基因高表达能对抗缺氧／复氧对心肌细胞的损伤，这一作用与其能抗细胞Ca^2＋负荷有关。

Heat Shock Protein 70 Gene Protects Rat Myocardium Cell against Anoxia-Reoxygeneration Injury

Objective:Many studies showed that the expression of heat shock protein 70 induced by heat stress are associated with protection against ischemia-reperfusion injury.But the protective effects may be confused by other factors in the same stress.To study the protective role of HSP70 expression in acute myocardial A/R injury,the liposome-mediated gene transfer technique was used for the transfection of pCDNA HSP70 into the neonatal rat myocardial cells.In addition,heat shock stress cytoprotection was also inve...