P2Y receptors belong to the G-protein coupled receptor superfamily. P2Y receptors mediate the actions of the extracellular nucleotides (ATP, ADP, UTP and UDP) and regulate several physiological responses, among them, cardiac function, platelet aggregation and SMC proliferation¹.

The mammalian P2Y family currently includes eight functional receptors; P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, P2Y12, P2Y13, and the UDP-glucose receptor, now renamed P2Y14^2-4.

The P2Y2 receptor is abundantly expressed in the apical membranes of several epithelial tissues including airway⁵. It has become a leading target for the treatment of cystic fibrosis. Activation of P2RY2 increases Cl^- efflux and mucociliary clearance, effects that might relieve symptoms of cystic fibrosis. P2Y2 agonist therapy is tested in an attempt to bypass the dysfunctioning CFTR channel. Several P2Y2 receptor agonists, especially INS37217, being evaluated as possible targets for the treatment of cystic fibrosis.⁶