运动对1型糖尿病大鼠心肌细胞中磷酸受纳蛋白表达的影响

Effects of Exercise on Expression of Phopholamban in the Myocardium Cells of Type 1 Diabetes Mellitus Rat

目的观察运动对1型糖尿病大鼠心肌细胞中磷酸受纳蛋白(PLB)表达影响及其意义。方法40只健康SD大鼠随机分为正常对照组、运动对照组、糖尿病组及糖尿病+运动组4组,每组10只。糖尿病大鼠模型复制成功后第4天开始跑台运动,于运动第4周末心脏采血收集血清,放射免疫法测定血清胰岛素水平,RT-PCR和Western-blotting法检测心肌细胞中磷酸受纳蛋白的表达。结果与正常对照组比较,糖尿病组血糖、糖化血清蛋白水平升高(P<0.01),血清胰岛素水平降低(P<0.01),心肌细胞PLB mRNA和蛋白表达无显著变化(P>0.05),糖尿病+运动组血糖及糖化血清蛋白水平均升高(均P<0.01),心肌细胞中PLB mRNA和蛋白表达上调(P<0.01)。与糖尿病组比较,糖尿病+运动组血糖及糖化血清蛋白水平均降低(均P<0.05),PLB mRNA和PLB蛋白表达水平均升高(均P<0.05)。结论运动对1型糖尿病大鼠心肌损伤有防治作用,其机制与运动能上调PLB基因表达可能有关。

Objective To Observe the effect and the significance of exercise on expression of phopholamban（PLB） in the myocardium cells of type 1 diabetes mellitus rat. Methods Forty healthy SD rats were randomly divided into four groups： normal control group; exercise training group, diabetes group and diabetes with exercise-training group, with ten rats in each group. At 4 days after the modle of type 1 diabetes mellitus rat was successfully set up, the rats were trained to run on a flat roof. At the end of 4-week-exercise training, the animals were let blood from their hearts and the level of blood insulin was tested by radiation-immunoreaction. The expression of PLB in the myocardium ceils was measured by reverse transcription-polymerase chain reaction and Western-blotting. Results Compared with the normal control group, the levels of blood glucose and glycosylated serum protein in the diabetes group increased（P〈0.01）, and insulin decreased（P〈0.01）. The expressions of PLB mRNA and PLB protein in the cardiomyocyte did not changed significantly（P〈0.05）;the levels of blood glucose and glycosylated serum protein in the diabetes with exercise training group increased （P〈0.01 ,respectively）;the expression of PLB mRNA and PLB protein in the cardiomyocyte increased （P〈0.01）. Compared with the diabetes group, the level of blood glucose and glycosylated serum protein in the diabetes with exercise training group decreased （P〈0.05,respectively）;the levels of PLB mRNA and PLB protein increased （P〈0.05, respectively）. Conclusion Exercise exert a good protective effects on the myocardium injure with type 1 diabetes mellitus rat, and the mechanism may be associated with exercise＇s up-reguation to gene expression of PLB.