胰岛素对糖尿病大鼠模型的心肌病理改变及TGF-β1、collagenⅢ表达的影响

摘要

目的 探讨胰岛素对糖尿病大鼠模型的心肌病理改变及TGF-β1、胶原蛋白Ⅲ(collagenⅢ)表达的影响.方法 将30只SD大鼠分别分为A、B、C组,每组10只,A组为对照组,B、C两组腹腔注射链脲佐菌素建立糖尿病大鼠模型,A、B组给予1 mL生理盐水腹腔注射,C组腹部皮下注射胰岛素.三组大鼠造模5周后处死,检测三组大鼠的血糖和血脂的变化,观察大鼠心肌的变化,TGF-β1、collagenⅢ的表达情况.结果①血糖、血脂改善:B、C两组大鼠的三酰甘油(TG)、总胆固醇(TC)均显著高于A组(P ＜ 0.05).C组的血糖、TG、TC、低密度脂蛋白胆固醇(LDL-C)显著低于B组(P ＜ 0.05),高密度脂蛋白胆固醇(HDL-C)显著高于B组(P ＜ 0.05).②心肌病理学改变:A组大鼠心肌细胞结构正常;B组大鼠心肌细胞排列紊乱,局灶性心肌纤维溶解,可见变性、坏死;C组大鼠心肌细胞排列比较完好,无明显的溶解断裂,无变性坏死;③因子、蛋白表达:B、C两组大鼠心肌组织中的TGF-β1、collagenⅢ表达显著高于A组(P ＜ 0.05).但C组中的TGF-β1、collagenⅢ表达显著低于B组(P ＜ 0.05).结论 胰岛素可调节糖尿病大鼠的糖、脂质代谢紊乱,降低的心肌病变程度,其机制可能与其降低了心肌组织中TGF-β1及collagenⅢ的表达有关.%Objective To investigate the influence of insulin on myocardial pathological changes and TGF-pl, collagen IH expression of diabetes rat model. Methods 30 SD rats were divided into group A, B, C, n = 10, group A was the control group, group B, C were intraperitoneal injection of streptozotocin to establish diabetic rats model. Group A, B was given 1 mL intraperitoneal injection of saline, group C was given abdominal subcutaneous injection of insulin. Three groups of rats were sacrificed after 5 weeks of modeling, the blood glucose and lipid changes of rats among three groups were detected, and the rat myocardial changes, TGF-pl, collagen IH expression were observed. Results (T)The blood glucose, blood lipid, improving: TG, TC of rats in group B and C were significantly higher than that of group A (P < 0.05). TG, TC, LDL-C blood glucose in group C were significantly lower than those in group B (P < 0.05), high density lipoprotein HDL-C was higher than that in group B (P < 0.05). ?The pathologic changes of myocardial: the myocardial cell structure of rats in group A was normal; in group B, myocardial cells of rats were arranged in disorder, focal myocardial fiber was dissoluted, with visible degeneration, necrosis; in group C, rat myocardial cells were arranged relatively intact, there were no significant dissolution fracture, no degeneration and necrosis. (3)The factor, protein expression: in group B, C, myocardium of rats with TGF-pl collagen IH expression was significantly higher than that in group A (P < 0.05). But in group C, TGF-pl, collagen IH expression was significantly lower than that of group B (P < 0.05). Conclusion Insulin can regulate diabetes rat carbohydrate, lipid metabolism disorders, reduce myocardial lesions, and its mechanism may be related to reduced myocardial tissue of TGF-p 1 and collagen IH expression.