RESUMEN
Objective To investigate the protective effect of insulin glargine in myocardium of diabetic rats. Methods Male Wistar rats were randomly divided into normal control group (NC), diabetes mellitus group After 6 weeks, we weighed rats and calculated the heart body weight ratio (H/B), Immunohistochemical technique was used to estimate the expression of transforming growth factor beta 1 (TGF-β_1) and the type-Ⅲ collagen (collagen Ⅲ). Myocardial pathologic changes were observed under expression of TGF-β_1 and collagen Ⅲ of DM group and DI group were significantly higher than those in NC group (P<0.05); the levels of H/B and the expression of TGF-β_1 and collagen Ⅲ of DI group were lower than myofibrils were arranged disorderly, mitochondria increased, with swelling and degeneration, while the changes of myocardial ultrastructure were obviously lightened after treatment with insulin glargine. Conclusion Insulin glargine may partly suppress the increased expression of TGF-β_1 and collagen Ⅲ in myocardial of diabetic rats, and it may decrease significantly the myocardial injury of diabetic rats.