P2Y Receptor

P2Y receptors are G-protein-coupled receptors (GPCRs) for extracellular nucleotides. There are eight human P2Y receptor subtypes (P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, P2Y12, P2Y13, and P2Y14. P2Y receptors are also found in many animal species indicating their development early in evolution. Almost all human cells express P2Y receptors. Human mast cells express P2Y12, an adenosine diphosphate receptor, and knockdown of this receptor impaired the LTE4-elicited production of MIP-1β and PGD2 in LAD2 human mast cells without altering their responses to LTD4. LTE4 induces the activation of ERK1/2 in CHO cells expressing P2Y12, which is sensitive to PTX. GPR99, which belongs to the P2Y receptor subfamily, was initially identified as a receptor for α-ketoglutarate. Because the α-ketoglutarate–dependent inositol phosphate formation in GPR99-expressing cells is insensitive to PTX, GPR99 seems to act via a Gq/11 pathway.
 The ADP-induced platelet aggregation mediated by P2Y1 and P2Y12 receptors. Active metabolites of the thienopyridine compounds ticlopidine, clopidogrel and prasugrel as well as the nucleoside analogue ticagrelor block P2Y12 receptors and thereby platelet aggregation. These drugs are used for the prevention and therapy of cardiovascular events. P2Y receptors play important roles in the nervous system. Adenine nucleotides modulate neuronal activity and neuronal fibre outgrowth by activation of P2Y1 receptors and control migration of microglia by P2Y12 receptors. UDP triggers microglial phagocytosis through activation of P2Y6 receptors. Interestingly, recent findings reveal a prominent role for P2Y2 receptors in Alzheimer's disease pathology. Based on pharmacology, signal transduction and structural similarity, P2Y receptors are divided into two subfamilies. The receptors of the first subfamily (consisting of the P2Y1, P2Y2, P2Y4, P2Y6 and P2Y11 receptors) couple via Gq-proteins to stimulation of phospholipase C followed by increases in inositol phosphates and mobilisation of Ca2+ from intracellular stores. P2Y11 receptors couple in addition to Gs proteins followed by increased adenylate cyclase activity.

References

1.von Kügelgen I,et al. Neuropharmacology. 2016;104:50–61.