实验性1型糖尿病大鼠心肌和肾组织纤维化的病理改变

Pathologic changes of myocardial and renal fibrosis in type 1 diabetes mellitus rats

目的探讨实验性1型糖尿病大鼠心肌和肾组织结构的病理变化和特点。方法一次性腹腔注射链脲佐菌素65 mg·kg-1建立大鼠1型糖尿病模型,第12周检测大鼠心肌和肾组织羟脯氨酸(HP)水平,免疫组织化学法分析胶原蛋白(CollagenⅠ、CollagenⅢ)在心肌和肾组织的分布及表达,进行心肌、肾组织光镜与电镜观察,并与同龄正常大鼠(对照组)相比较。结果与对照组比较,模型组大鼠心肌和肾组织纤维化指标HP、CollagenⅠ、CollagenⅢ的表达均显著增高(P<0.05)。电镜发现模型组大鼠心肌细胞肌丝稀疏,线粒体肿胀,间质胶原增生;肾组织肾小球毛细血管基底膜弥漫性增厚,间质胶原增生。结论早期糖尿病大鼠模型已出现心和肾纤维化改变,而且二者的病理改变基本同步。

Objective To investigate the myocardial and renal pathomorphology at same stage of type 1 diabetes melli- tus（DM） rats. Methods The type 1 DM rat model was induced by a single intraperitoneal injection of streptozotocin at a dose of 65 mg kg^-1 body weight. At 12 weeks after DM was induced, the myocardial and renal hydroxyproline （HP） were performed. The Collagen I and collagen Ill protein expressions were evaluated by qualitative and semiquantitative immunohistochemical staining. The myocardial and renal pathomorphology change were observed with light microscope and transmission electron microscope. The age-matched normal rats served as control group. Results Compared with control group, HP, Collagen I and Collagen HI in heart and kidney were increased significantly in model gTOup（P 〈0.05）. Myofilament rarefaction,mitro- chondrial swelling, interstitial collagen hyperplasia were observed in DM rats by electron microscope. Diffuse thickening of glo- merular capillary basement membrane and interstitial collagen hyperplasia were observed in DM rats by electron microscope. Conclusion Pathologic changes of myocardial and renal fibrosis has been observed in the early DM rat models. And the path- ologic changes of both are synchronous.