P2Y purinergic receptor-regulated insulin secretion is mediated by a cAMP/Epac/Kv channel pathway

Biochem Biophys Res Commun. 2015 May 8;460(3):850-6. doi: 10.1016/j.bbrc.2015.03.121. Epub 2015 Apr 1.

Abstract

Enhancement of insulin secretion is a major therapeutic approach for type 2 diabetes (T2D). Activation of P2Y purinergic receptor (P2YR) causes potentiation of insulin secretion in a glucose-dependent manner, making it a promising therapeutic target for T2D. Here we show that activation of P2YR to potentiate insulin secretion is mediated by adenylyl cyclase/cyclic AMP (cAMP) and the downstream effector, exchange protein directly activated by cAMP (Epac), leading to inhibition of voltage-dependent potassium (Kv) channels. P2YR-mediated Kv channel inhibition results in prolongation of action potential duration, and in turn elevates intracellular Ca(2+) level and insulin secretion. Taken together, the data indicate that cAMP/Epac/Kv channel pathway mediates P2YR-regulated insulin secretion, which may have important therapeutic implications for T2D.

Keywords: Cyclic AMP; Diabetes; Insulin secretion; P2Y purinergic receptor; Voltage-dependent potassium channels.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism
  • Cyclic AMP / metabolism*
  • Guanine Nucleotide Exchange Factors / metabolism*
  • Insulin / metabolism*
  • Insulin Secretion
  • Islets of Langerhans / metabolism
  • Male
  • Patch-Clamp Techniques
  • Potassium Channels / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Purinergic P2Y / physiology*
  • Signal Transduction

Substances

  • Guanine Nucleotide Exchange Factors
  • Insulin
  • Potassium Channels
  • Rapgef3 protein, rat
  • Receptors, Purinergic P2Y
  • Cyclic AMP
  • Calcium