Abstract: AIM: To explore the protective effects of the nonenzymation glycosylation inhibitor-aminoguanidine (AG)on the cardiac function and ultrastructure in diabetes-induced rats.METHODS: Sprague-Dawley rats were randomly divided into control group, sreptozotocin(STZ)-induced diabetic group and aminoguanidine treated diabetic group (150 mg·kg^-1·d^-1 water given after diabetes induced).The serum fructosamine content levels and the cardiac mass index and some related parameters were determined at 12 weeks.RESULTS: The serum fructosamine content levels and the cardiac mass were higher than that in the control group. The value of±dp/dt_max tite was decreased in diabetic group at 12 weeks compared with the control group. Electron microscopic morphometry of heart samples revealed typical diabetic alterations consisting in a focal loss, disorganization of myofibril, mitochondril swelling, and lysis of cistae. In AG treated group, The serum fructosamine content levels and the cardiac mass decreased, the value of±dp/dt_max was increased markedly compared with diabetic rats. Microvascular membrane, proliferation of the collegen in the extracellular matrix and nyocardial ultrastructure were better than diabetes.CONCLUSION: There are changes of myocardial function, ultrastractue abnormalities and ventricular hypertropfhy in diabetic rats. AG can inhibit the progress of diabetic cardiomyopathy.

Key words: aminoguanidine, nonenzymation glycosylation, diabetic rat, cardiomyopathy