摘要
目的观察糖尿病性心肌病(DCM)大鼠心脏结构与功能、循环及心肌局部血管紧张素Ⅱ(AngⅡ)的变化,探究AngⅡ在DCM发病中的作用。方法 30只SD大鼠随机分为DCM组和对照组,DCM组大鼠给予一次性腹腔注射链脲佐菌素(STZ,65mg/kg)诱导糖尿病模型,建模成功后16周后应用动物心脏超声检测心脏结构及功能的变化,HE染色及天狼猩红染色观察心肌病理改变,放射免疫法检测循环中AngⅡ的水平,心肌组织冰冻切片免疫荧光染色观察心肌局部AngⅡ的表达。结果相较于对照组,DCM组大鼠左室舒张末期直径(LVEDd)、左室收缩末期直径(LVESd)、左室舒张末期容积(LVEDv)、左室收缩末期容积(LVESv)均增大,左心室射血分数(LVEF)减低,两组的差异有统计学意义(P<0.05),HE及天狼猩红染色可见DCM组大鼠心肌细胞排列紊乱、肥大、边界不清,胶原生成增加,同时血浆及心肌局部AngⅡ水平显著增加,且血浆AngⅡ水平与心肌胶原含量呈正相关关系(r=0.907,P<0.05)。结论 AngⅡ可能通过促进心肌纤维化过程参与DCM发生。
Objective To explore the changes of cardiac structure and function in streptozotocin （STZ）- induced diabetic cardiomyopathy （DCM） rats so as to detect the level of angiotensin Ⅱ（Ang Ⅱ ） in blood and the myocardium and illuminate the role of Ang Ⅱ in DCM. Methods We randomly divided 30 SD rats into control group and DCM group （which received a single injection of streptozotocin, 65 mg/kg）. The changes of cardiac structure and function were observed by ultrasonic cardiogram at the end of 16 weeks after injection. Then the changes in the myocardium were also analyzed by using hemotoxylin and eosin staining and Sirius red staining. The level of Ang Ⅱ in blood was tested by radioimmunoassay. The expression of Ang Ⅱ in the myocardium was detected by immunofluorescence. Results Compared with those of the controls, the hearts were dilated in DCM rats accompanied with cardiac dysfunction. There were significant increases in LVEDd, LVESd, LVEDv, and LVESv but decrease in LVEF （P〈 0.05）. There were arrangement disorder and hypertrophic cardiomyocytes in DCM. Then the fibrosis area of DCM was significantly increased compared with that of the controls. The level of Ang Ⅱ in blood and myocardium was significantly higher in DCM than in controls, At the same time, Pearson analysis revealed that the level of Ang Ⅱ in blood was positively related to the collagen content of myocardiurn （r =0. 907, P〈0.05）. Conclusion Our study provides experimental evidence that Ang Ⅱ plays an important role in myocardial fibrosis of DCM.
出处
《西安交通大学学报（医学版）》
CAS
CSCD
北大核心
2016年第2期199-203,共5页
Journal of Xi’an Jiaotong University（Medical Sciences）
基金
国家自然科学基金资助项目(No.81170209)~~
