The adenosine receptors are a class of purinergic G protein-coupled receptors with adenosine as endogenous ligand. There are four known types of adenosine receptors in humans: A1, A2A, A2B and A3; each is encoded by a different gene. The A2A receptor is abundant in basal ganglia, vasculature, T lymphocytes, and platelets and it is a major target of caffeine, which is a competitive antagonist of this protein.

The receptor is available in the following formats: stable over-expression cell line, membrane preparation, or purified receptor in HEK293 or CHO. Various tagged versions are available.