Adenosine

Adenosine is a purine nucleoside that serves as an endogenous ligand of a family of four adenosine receptors, which serve diverse roles related to smooth muscle tone, central nervous system regulation, and cardiac function. Adenosine is one of four nucleoside building blocks to RNA, which is essential for all life. Adenosine is a precursor for adenosine 5’-monophosphate, adenosine 5’-diphosphate, adenosine 5’-triphosphate and cyclic AMP.