Expression and Signaling of β-Adrenoceptor Subtypes in the Diabetic Heart

Diabetes is a chronic, endocrine disorder that effects millions of people worldwide. Cardiovascular complications are the major cause of diabetes-related morbidity and mortality. Cardiac beta(1)- and beta(2)-adrenoceptor (AR) stimulation mediates positive inotropy and chronotropy, whereas beta(3)-AR mediates negative inotropic effect. Changes in beta-AR responsiveness are thought to be an important factor that contributes to the diabetic cardiac dysfunction. Diabetes related changes in beta-AR expression, signaling, and beta-AR mediated cardiac function have been studied by several investigators for many years. In the present review, we have screened PubMed database to obtain relevant articles on this topic. Our search has ended up with wide range of different findings about the effect of diabetes on beta-AR mediated changes both in molecular and functional level. Considering these inconsistent findings, the effect of diabetes on cardiac beta-AR still remains to be clarified.