ABSTRACT
AIM:To investigate the changes of cardiac structure and function in rats with type 2 diabetic melli-tus(T2DM),and to explore the mechanisms underlying diabetic cardiomyopathy.METHODS:The cardiac structure and function were measured by echocardiography in Zucker diabetic fatty(ZDF)rats and their control Zucker lean(ZL)rats. The size of the cardiomyocytes was determined by wheat germ agglutinin staining.The protein expression of atrial natriuretic peptide(ANP),β-myosin heavy chain(β-MHC), receptor for advanced glycation end products(RAGE), L-type cal-cium channel α1C subunit(CaV1.2)and Orai1 was assessed by Western blot.RESULTS:Compared with the ZL control rats,the thickness of left ventricular wall,ejection fraction(EF),fractional shortening(FS)and the sizes of cardiomyo-cytes were significantly increased,and diastolic function was decreased in the ZDF rats(P<0.05).The protein expression of β-MHC, ANP, RAGE and Orai1 was increased, while the expression of Ca V1.2 was decreased in ZDF rats(P <0.05).CONCLUSION:T2DM rats show the prominent features including cardiomyocyte hypertrophy,ventricular hyper-trophy and compensatory enhancement of cardiac function, and the Ca2+handling and increase in RAGE expression may play important roles in the processes.