Impact of drug intervention on cardiomyopathy in STZ-induced type 1 diabetic rats / 中国综合临床

ABSTRACT

Objective To investigate the pathological changes of myocardium in diabetic rats and the effect of aspirin, perindopril, prednisone on the pathological changes of myocardium in type 1 diabetic rats. Methods Thirty SD rats were randomly divided into the following groups ( 1 ) diabetes mellitus (DM)group ( n = 20) treated with intraperitoneal injection of streptozocin (STZ) 60 mg/kg at one time, diluted in sodium citrate buffer. (2) normal control group (n = 10) intraperitoneal injection of sodium citrate buffer. The blood glucose and the weight were measured regularly for 8 weeks. The 20 diabetic model rats were randomly divided into four groups (n = 5 individually), from the 4th day, the rats were given normal saline dissolved aspirin, perindopril, prednisone gavage respectively, and the normal control group and diabetic group were given an equal volume of saline daily gavage. After 8 weeks, the pathological changes in the cardiac muscle tissue were observed under light microscope and electron microscope. Results Three days after the injection of STZ, the blood glucose in the DM group was higher than 16. 7 mmol/L,20 rats were all modeling successfully. The model rats suffered from polydipsia, polyphagia, polyuria and weight loss significantly. HE staining showed diabetic myocardial cell swell, hypertrophy, degeneration and significant nuclear enlargement; the myocardial fiber fractured,dissolved, contraction wavy and disorganized fibre infiltrated by inflammatory cells. Under electron microscope, diabetic myocardial muscle fibers arranged irregularly, fractured and dissolved; the glycogen between the muscle fiber accumulated, mitochondria swelled, most of the ridges in mitochondria were not clear, cell plate widened. Compared with the diabetic group, the above-mentioned pathological changes reduced in the drug intervention group,and the changes in perindopril group was most significant. Conclusion Injection of STZ 60 mg/kg could successfully induce diabetic in rats and held stable blood glucose level. After 8 weeks, diabetes could cause servere damages in myocardium in the rats, but aspirin, perindopril, prednisone could reduce the cardiomyopathy in diabetic rats,in which perindopril had more positive effect.