糖尿病大鼠代谢改变与糖尿病心肌病关系研究

The role of metabolic alteration in the pathogenesis of diabetic cardiomyopathy

目的 :(1)观察糖尿病大鼠血糖及血脂代谢的改变 ;(2 )观察糖尿病大鼠心肌形态的变化 ;(3 )探讨糖尿病大鼠代谢改变与糖尿病心肌病的关系。方法 :本实验的对象为Wistar大鼠。所有糖尿病大鼠的空腹血糖均大于 16 7mmol/L。为探讨糖尿病心肌病与大鼠代谢改变的关系 ,将大鼠随机分为 6w组和 12w组 ,6w组和 12w组又分为正常对照组和糖尿病组。各组实验结束时测定下列参数 :代谢控制情况 (血糖、糖化血红蛋白、游离脂肪酸、甘油三脂和总胆固醇 )、血流动力学 (心率、收缩压、舒张压和平均动脉压 ) ;把左室重量 /体重(即心系数 )作为反映糖尿病心肌病左室肥厚严重程度的一个指标。结果 :(1) 6w和 12w时 ,糖尿病对照组心系数明显高于正常对照组 (P <0 0 5 )。 (2 )糖尿病组大鼠发生明显的糖代谢紊乱 ,血糖和糖化血红蛋白水平均明显高于正常组大鼠 (P <0 0 5 ) ,糖尿病组大鼠总胆固醇和甘油三脂高于正常对照组 (P <0 0 5 ) ,糖尿病对游离脂肪酸水平无影响。 (3 )血流动力学各指标 (心率、舒张压、收缩压和平均动脉压 )在各组之间无统计学差异。结论 :(1)糖尿病心肌病的典型特征之一为左室肥厚 ;(2 )本实验中 ,糖尿病的代谢紊乱与糖尿病心肌病的发病有关 ;(3 )

Objective:To investigate the relationship between the metabolic alteration and the diobetic cardiomyopathy in diabetic rats.Methods:In the study,the STZ was used to induce the diabetic mellitus,and the fasting glucose of all diabetic rats should beyond the 16 7mmol/L.Wistar rats were divided randomly into three groups:basic control,6w group including control and diabetic rats,and so did 12w group.control and diabetic rats were under sendetary condition,the duration of experiment was 6～12w.For each experiment,the effects of the various treatment protocols on the severity of the diabetic state were assessed by measuring blood glycosylated hemoglobin(gHb) and plasma levels of glucose,free fatty acids,triglcerides,and total cholestrol.To test the response of the heart to the element of diabetic,heart rate,systolic blood pressure and diastolic blood pressure were also measured,so did the weight of heart and left ventricular.We regarded the ratio between left ventricular weight and body weight,also the heart weight index,as the factor reflecting the severity of left ventricular hypertrophy.Results:1 The heart weight index was higher significantly( P <0 05) in 6w diabetic when compared with age matched controls,so was it in the 12w diabetic groups when compared with controls.2 The metabolic disorders of carbohydrate were significant in diabetic rats,analysis of plasma from diabetic rats showed increases in glucose,glycosylated hemoglobin,triglycerides and total cholestrol ( P <0 05) except for the free fatty acids.3 However,the haemodynamic parameters,such as heart rate,systolic blood pressure and diastolic blood pressure,were not different significantly among groups,and there was no correlation between the heart weight index and haemodynamic alterations( P >0 05).Conclusion:The left ventricular hypertrophy is one of the characteristics of diabetic cardiomyopathy.The metabolic disorders play a role in the pathogenesis of diabetic cardiomyopathy,whereas the role of haemodynamic parameters in the development of diabetic cardiomyopathy is not sufficient and clear.