Cardiac β-Adrenoceptor Expression Is Reduced in Zucker Diabetic Fatty Rats as Type-2 Diabetes Progresses

Reduced cardiac β-adrenoceptor (β-AR) expression and cardiovascular dysfunction occur in models of hyperglycemia and hypoinsulinemia. Cardiac β-AR expression in type-2 diabetes models of hyperglycemia and hyperinsulinemia, remain less clear. This study investigates cardiac β-AR expression in type-2 diabetic Zucker diabetic fatty (ZDF) rats.H]CGP12177 were performed in Zucker lean (ZL) and ZDF rats at 10 and 16 weeks of age as diabetes develops. Blood glucose, body mass, and diet consumption were measured. Western blotting of β-AR subtypes was completed in parallel. Echocardiography was performed at 10 and 16 weeks to assess systolic and diastolic function. Fasted plasma insulin, free fatty acids (FFA), leptin and fed-state insulin were also measured.-AR remained elevated, similar to 10 weeks (112±9%). While HR was reduced at 10 and 16 weeks in ZDF rats, no significant changes were observed in diastolic or systolic function.-AR expression are inversely correlated with the progression of type-2 diabetes