HSP70在严重烧伤大鼠心肌中的表达及其保护作用的研究

Expression of heat shock protein 70 in myocardium of severely burned rats and its protective effect

目的 研究热休克蛋白 70 (HSP70 )在严重烧伤大鼠心肌中的表达变化规律 ,并观察诱导热休克反应对烧伤后心肌损害的保护作用。方法 72只Wistar大鼠随机分为单纯烫伤组 (B组 )、亚砷酸钠预处理组 (SA组 ) ,于致伤前及3 0 %TBSAⅢ度烫伤后 3、6、12、2 4、48h检测血清心肌钙蛋白I含量变化 ,Westernblot检测心肌组织HSP70蛋白表达情况。结果 大鼠严重烧伤后 3h心肌组织HSP70蛋白表达显著升高 ,伤后 48h达高峰。大鼠烫伤后 3h血清心肌钙蛋白I(cT nI)含量即开始明显升高 ,伤后 12h达高峰。亚砷酸钠预处理可显著诱导机体的热休克反应 ,SA组伤后多数时相点血清cTnI含量显著低于B组 ,且波动幅度较小。结论 严重烧伤早期即可引起心肌组织HSP70蛋白表达显著增强 。

Objective To study the expression of heat shock protein 70 (HSP70) in myocardium and the protective effect of heat shock response on myocardium of scalded rats. Methods A total of 72 Wistar rats were randomly divided into 2 groups: simple burn group (B group) and sodium arsenite pretreatment group (SA group). Changes of serum cardiac troponin I(cTnI) content were determined at 0, 3, 6, 12, 24 and 48 h after 30% full thickness scald injury. Samples of myocardium were taken for the determination of HSP70 expression by Western blot analysis. Results HSP70 expression in myocardium increased significantly at 3 h after scald injury. The level of HSP70 was highest at 48 h after scald. Serum cTnI content increased significantly at 3 h after scald injury and reached the peak at 12 h after scald injury. Heat shock response could be induced by sodium arsenite pretreatment. SA group showed a significantly lower serum cTnI content. Conclusion Severe burn injury causes a significantly increased expression of HSP70 in myocardium. HSP70 may have endogenous anti injury effect on early burn injury of the myocardium.