PI3K is involved in P2Y receptor-regulated cAMP /Epac/Kv channel signaling pathway in pancreatic β cells

Abstract

P2Y receptors (P2YR) are a family of purinergic G protein-coupled receptors, which could be stimulated by extracellular nucleotides. In pancreatic β cells, activation of P2YR has long been shown to stimulate insulin secretion in a glucose-dependent manner. Previously, we reported that P2YR-modulated insulin secretion is mediated by a cAMP/Epac/Kv channel pathway. However, the interaction between Epac and the Kv channel in P2YR-modulated insulin secretion remains unclear. In this study, we used patch-clamp technique and insulin secretion assay to investigate the potential molecules that may link Epac to Kv channel inhibition induced by P2YR activation. We identified that phosphatidylinositide 3-kinase, which mediates P2YR-regulated insulin secretion, is a critical mediator between Epac and the Kv channel.

Keywords: Epac; Insulin secretion; P2Y purinergic receptor; Phosphatidylinositide 3-kinase; Voltage-dependent potassium channels.