长期运动预适应模型大鼠心脏蛋白激酶C和热休克蛋白70的表达

背景：研究表明蛋白激酶C和热休克蛋白70可能参与运动预适应的心脏保护作用。目的：观察长期运动预适应对大鼠心脏蛋白激酶C和热休克蛋白70的影响及其对心脏保护的作用机制。方法：将SD大鼠随机分为对照组,力竭运动组和运动预适应组。对照组和力竭运动组大鼠常规饲养3周,运动预适应组大鼠进行3周的间歇性游泳运动建立长期运动预适应动物模型。3周后,力竭运动组和运动预适应组大鼠进行一次性力竭游泳运动。结果与结论：大鼠力竭运动后,力竭运动组心脏热休克蛋白70表达高于对照组（P〈0.05）;先经3周运动预适应再进行力竭运动后,运动预适应组心脏蛋白激酶C和热休克蛋白70的表达高于力竭运动组（P〈0.05）。结果证实,长期运动预适应能激活心脏蛋白激酶C,诱导热休克蛋白70的合成增多,从而发挥其心脏保护作用。

Expression of protein kinase C and heat shock protein 70 in the heart of rat models of long-term exercise preconditioning

BACKGROUND：Several studies have demonstrated that protein kinase C （PKC） and heat shock protein 70 （HSP70） take part in the cardioprotection of exercise preconditioning （EP）, but the relationship and the underlying mechanism remain poorly understood. OBJECTIVE：To investigate the effects of long-term EP on PKC and HSP70 expression in the rat heart and the possible mechanism of cardioprotection. METHODS：Sprague-Dawley rats were randomly divided into the control, exhausted exercise and EP groups. Rats in the control and exhausted exercise groups were fed normally for 3 weeks. The EP group rats underwent 3 weeks of intermittent swimming exercise in order to establish long-term EP animal model. After 3 weeks, the exhausted exercise group and exercise preconditioning group underwent exhausted exercise. PKC and HSP70 expression in rat heart was determined by western blot analysis and immunohistochemistry.RESULTS AND CONCLUSION：After exhausted exercise, cardiac HSP70 expression was greater in the exhausted exercise group than in the control group （P 0.05）. After 3 weeks of EP and subsequent exhausted exercise, cardiac PKC and HSP70 expression was greater in the EP group than in the exhausted exercise group （P 0.05）. The results demonstrated that long-term EP could activate cardiac PKC expression and induce HSP70 synthesis, which could play a big role in cardioprotection of long-term EP.