Adenosinergic system

The "adenosinergic system" collectively refers to the ensemble of molecular components, primarily adenosine receptors (A1, A2A, A2B, A3), enzymes (such as adenosine deaminase and adenosine kinase), transporters, and the endogenous ligand adenosine itself. This system regulates numerous physiologic processes including neurotransmission, vasodilation, cardiac conduction, and immune modulation. The system is not a single druggable target, but rather a regulatory network with multiple potential pharmacological intervention points. The adenosinergic system centers on adenosine as a signaling molecule that activates four main G protein-coupled receptors (GPCRs): adenosine A1 receptor (A1R), adenosine A2A receptor (A2AR), adenosine A2B receptor (A2BR), and adenosine A3 receptor (A3R). Each is a distinct, canonical therapeutic target with its specific structure, function, and pharmacology. Drugs typically target specific adenosine receptor subtypes, not the system as a whole. Examples include adenosine (the molecule), adenosine analogs, and receptor agonists/antagonists for A1, A2A, A2B, or A3 receptors. Mechanisms of action and biomarkers are defined at the receptor or enzyme level (e.g., inhibition of A2A receptor), not at the system/network level. Safety concerns are typically linked to receptor subtype modulation (e.g., bradycardia with A1R agonists, hypotension with general agonists), and will differ by intervention point. "Adenosinergic system" is not a canonical molecular target. To enable structured annotation, use specific adenosine receptor subtypes (such as "Adenosine A2A receptor") or specific enzymes within this system. This entry should be flagged as too broad and not a valid single molecular drug target.

Other names

Adenosine signaling systemAdenosine systemPurinergic P1 systemAdenosine receptor system