链脲佐菌素糖尿病仓鼠心肌病变的病理变化

Pathologic Changes of Diabetic Cardiomyopathy in STZ-induced Diabetic Hamsters

目的 观察链脲佐菌素 (STZ)诱导糖尿病仓鼠机体代谢及心肌病理改变 ,建立一种理想的糖尿病心肌病变动物模型。方法 腹腔注射STZ建立糖尿病仓鼠动物模型 ,10周后电镜观察心肌超微结构 ,光镜观察心肌病理改变 ,免疫组化法检测心肌Ⅰ、Ⅲ型胶原变化 ,同时应用生化、放免法检测血糖、糖化血清蛋白、血脂、胰岛素变化。结果 与正常对照 (NC)组仓鼠相比 ,糖尿病 (DM )组仓鼠血糖和糖化血清蛋白水平显著升高 ;血TG、CHO和LDL也明显升高 ;病程 10周的糖尿病仓鼠表现为心肌内大量糖原颗粒沉积 ,心肌局灶性炎症细胞浸润和间质淡嗜伊红物质沉积 ;NC组仓鼠心肌Ⅰ、Ⅲ型胶原表达量为 1.92± 0 .2 7、1.11± 0 .12 ;DM组Ⅰ、Ⅲ型胶原表达量分别为NC组的 2 .71和 1.6 8倍 (P <0 .0 0 1、<0 .0 1) ,且Ⅰ /Ⅲ型胶原比值也明显升高 (P <0 .0 1)。结论腹腔注射STZ可诱导稳定的糖尿病仓鼠动物模型 ;糖尿病仓鼠机体代谢和心肌病理变化与人类相似 。

Purpose: To investigate the changes of general metabolism and myocardial pathology in streptozotocin (STZ)-induced diabetic hamsters, so as to set up a kind of ideal diabetic cardiomyopathy model. Methods: Diabetic state in hamsters was achieved by intraperitoneal injection (IP) of STZ 40 mg/kg once a day for 3 days. After stabilization of diabetic state for 10 weeks, the myocardial ultrastructure was observed with electron microscope and the pathologic changes were observed by microscope. Immunohistochemistry was used to measure the levels of expression of type I and type III collagen in diabetic and normal hamster hearts. Levels of blood glucose, glycated serum protein (GSP), lipoproteins and insulin were determined using biochemical or RIA methods. Results: Compared with NC group, levels of blood glucose, GSP, TG, CHO and LDL in DM group were much higher. Diabetic hamsters manifested glycogen deposition in hearts, local inflammatory cells infiltration and accumulation of extracellular matrix in interstitium. Levels of expression of collagen I and III in NC group were 1.92 ± 0.27 and 1.11 ± 0.12 respectively. Levels of collagen I and III in DM group were 2.71 and 1.68 higher than NC group (P < 0.001, < 0.01). And the ratio of collagen I/collagen III was much higher too (P < 0.01). Conclusions: Consistent diabetic hamster models can be established by intraperitoneal injection of STZ. Changes of general metabolism and myocardial pathology in diabetic hamsters are similar to human beings, so diabetic hamsters are ideal models to investigate human diabetic cardiomyopathy.