Cardiac myocyte adenosine receptors and caveolae

Abstract

The purine nucleoside adenosine exerts numerous effects in the mammalian heart, the most well-recognized being regulation of coronary blood flow and cardiac conduction. These effects are mediated via activation of G protein linked adenosine receptor subtypes, A2a and A1 receptors, located primarily on vascular cells and cardiac myocytes, respectively. Although adenosine A1 receptors are also expressed in ventricular myocytes, adenosine exerts no significant direct effects in these cells. A recent report from our laboratory indicates that ventricular myocyte A1 receptors are concentrated in caveolin enriched plasma membrane microdomains referred to as caveolae. This review focuses on these recent findings and their relevance to subcellular compartmentalization of A1 receptor signaling in ventricular myocardium. © 2001, Elsevier Science Inc.