不同强度运动对糖尿病大鼠心肌PAI-1及血清NO、NOS的影响

Effect of Exercise with Different Intensities on the Myocardial PAI-1 and Serum NO and eNOS in Diabetic Rats

目的:探讨不同强度运动对糖尿病大鼠心肌PAI-1(纤溶酶原激活物抑制剂-1)及血清一氧化氮(NO)、内皮型一氧化氮合酶(eNOS)、总一氧化氮合酶(T-NOS)的影响,分析运动防治糖尿病并发心肌病的生物学机制。方法:81只6周龄雄性SD大鼠经6周高脂高糖膳食喂养并腹腔注射链脲佐菌素建立糖尿病模型后,随机挑选43只分为糖尿病安静对照组(DMC)10只,糖尿病运动1组(DME1)、2组(DME2)和3组(DME3)各11只,3个运动组每天分别进行1 h速度为10 m/min(相当于30%VO2max)、15 m/min(相当于50%VO2max)、20 m/min(相当于70%VO2max)低、中、高三种强度跑台运动,5d/w,实验6周末检测存活的39只大鼠的血糖(FBG)、糖化血清蛋白(GSP)与胰岛素(FINS)等糖代谢相关指标和心肌纤溶系统指标心肌PAI-1,血清NO、eNOS、T-NOS。结果:与糖尿病安静对照组比较,3个运动组大鼠空腹血糖、糖化血清蛋白均降低,胰岛素敏感指数、胰岛素水平均升高,其中三运动组FBG下降有统计学意义(P<0.01),低、中强度运动组GSP下降有统计学意义(P<0.05),高强度组FINS上升有统计学意义(P<0.05)。与糖尿病安静对照组比较,低、中、高强度运动组大鼠心肌PAI-1均显著降低(P<0.05,P<0.01,P<0.01),血清NO显著升高(P<0.05,P<0.01,P<0.05),eNOS水平显著升高(P<0.05,P<0.01,P<0.01)。低强度运动组T-NOS升高有统计学意义(P<0.05)。结论:低、中强度运动能较好控制糖尿病大鼠血糖水平;不同强度有氧运动能改善糖尿病大鼠心肌PAI-1及血清NO、eNOS、T-NOS水平,对预防糖尿病心肌病的发生有一定意义。

Objective To study the effect of exercise with different intensities on the myocardial plasminogen activator inhibitor（PAI-1）and serum nitric oxide（NO）,endothelial nitric oxide synthase（eNOS）and total nitric oxide synthase（T-NOS）of diabetic rats,in order to understand the mechanisms of exercise in the preventing the diabetes.Methods Six-week old diabetic rats＇ model was established through 6-week high fat and high sugar diet,and intraperitoneal injection of streptozotocin,and then the rats were divided into 4 groups：sedentary group,exercise group 1,exercise group 2,and exercise group 3.Exercise groups underwent treadmill running 5 days per week for 6 weeks at the speed of 10m/min,15m/min and 20m/min,presenting the intensities of 30% O2max,50%VO2max and 70%VO2max respectively.The FBG,GSP,FINS,cardiac diastolic function and myocardial fibrinolytic parameters of myocardial PAI-1,serum NO,eNOS and T-NOS were tested.Results As compared with diabetic sedentary group,the FBG decreased significantly in three exercise groups（P〈0.01）,GSP and IRI decreased in DME1 and DME2 rats significantly（P〈0.05）,FINS elevated in DME2 rats（P〈0.05）significantly,myocardial PAI-1 in DME1,DME2 and DME3 rats decreased significantly（P〈0.05,P〈0.01,and P〈0.01,respectively）,serum NO increased（P〈0.05,P〈0.01,and P〈0.05,respectively）and eNOS increased（P〈0.05,P〈0.01,and P〈0.01,respectively）significantly.Conclusion Exercise with low and moderate intensities can control blood glucose level effectively.Aerobic exercise with different intensities improves the level of cardiac PAI-1 and serum NO,eNOS and T-NOS,demonstrating its preventive effect on diabetic cardiomyopathy.