Table 1. P2Y Receptor Function and Coupling to G proteins.

Receptor	Agonist	G protein—Main Effector(s)	Function
P2Y1	ADP	Gq—PLCβ, Rac, Rho activation	Platelet shape change/aggregation Bone resorption Leptin secretion from adipocytes Mechanical and thermal nociception Atherosclerosis Angiogenesis Synaptic plasticity
P2Y2	ATP/UTP	Gq—PLCβ activation Go—PLCβ, Rac activation G12—Rho activation	Inhibition of bone formation and mineralization Immune cell recruitment and phagocytosis Vascular tone, inflammation, thrombosis Blood pressure regulation Intraocular pressure regulation Mechanical and thermal nociception HIV infection of T cells Epithelial K+/Cl− secretion Pancreatic and renal functions Liver regeneration Wound healing
P2Y4	UTP	Gq—PLCβ activation Go—PLCβ activation	Visual and auditory transmission Intestinal K+/Cl− secretion
P2Y6	UDP	Gq—PLCβ activation G12/13—Rho activation	Bone resorption Vascular tone and inflammation Cardiac fibrosis Macrophage cytokine/chemokine release Microglial phagocytosis Epithelial Cl− secretion
P2Y11	ATP	Gq—PLCβ activation Gs—AC activation	Inhibition of neutrophil apoptosis Negative regulation of TLR signaling Pancreatic Cl− secretion Cell cycle arrest in endothelium
P2Y12	ADP	Gi/o—AC inhibition PLCβ, RhoA activation	Platelet aggregation Microglial activation/migration Dendritic cell activation/macropinocytosis Peripheral anti-nociception, central nociception
P2Y13	ADP	Gi/o—AC inhibition PLCβ, RhoA activation	Bone formation Liver uptake of HDL Inhibition of ATP release from RBCs Peripheral anti-nociception
P2Y14	UDP/UDP-glucose	Gi/o—AC inhibition PLCβ activation	Immune function/IL-8 release in epithelium Gastric function/stomach contractility Peripheral anti-nociception

Data derived from Refs 3,11–67.