Adenosine-d13 (Adenine riboside-d13; D-Adenosine-d13) is a deuterium-labeled form of Adenosine. Adenosine (Adenine riboside) is a widely present endogenous secretion that exerts effects via four G-protein-coupled receptors (A1, A2A, A2B, and A3). It influences nearly all aspects of cellular physiology, including neuronal activity, vascular function, platelet aggregation, and blood cell regulation.