Decreased intracellular chloride promotes ADP induced platelet activation through inhibition of cAMP/PKA instead of activation of Lyn/PI3K/Akt pathway

Biochem Biophys Res Commun. 2018 Sep 10;503(3):1740-1746. doi: 10.1016/j.bbrc.2018.07.107. Epub 2018 Aug 16.

Abstract

Decrease of chloride concentration contributes to cardiovascular diseases, however, whether decrease of chloride concentration is involved in platelet activation remains elusive. In the present study, we found that ACI patients had lower serum chloride which would be rescued after Aspirin administration. ADP induced chloride concentration reduction in platelets. Blockade of chloride channel prevented ADP-induced platelet adhesion, activation and aggregation, however, decreasing the extracellular chloride concentration promoted ADP-induced platelet adhesion and activation. Decrease of the extracellular chloride concentration facilitated the inactivation of Src family kinase Lyn, which was not involved in PI3K/Akt phosphorylation. Nevertheless, low chloride concentration promoted the production of platelet cytosol Gαi2 subunit. This subunit prevents AC from converting ATP into cAMP, which therefore, inhibited the phosphorylation of PKA to promote platelet activation. In conclusion, decreased intracellular chloride promotes ADP induced platelet activation through the Gαi2/cAMP/PKA pathway instead of the Lyn/PI3K/Akt signal pathway.

Keywords: ACI; Chloride; Gαi2; Lyn; PKA; cAMP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Diphosphate / metabolism*
  • Animals
  • Chlorides / blood
  • Chlorides / pharmacology*
  • Cyclic AMP / antagonists & inhibitors*
  • Cyclic AMP / metabolism
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors*
  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • Humans
  • Mice
  • Phosphatidylinositol 3-Kinases / metabolism
  • Platelet Activation / drug effects*
  • Platelet Aggregation Inhibitors / blood
  • Platelet Aggregation Inhibitors / pharmacology*
  • Proto-Oncogene Proteins c-akt / metabolism
  • Signal Transduction / drug effects*
  • src-Family Kinases / metabolism

Substances

  • Chlorides
  • Platelet Aggregation Inhibitors
  • Adenosine Diphosphate
  • Cyclic AMP
  • Phosphatidylinositol 3-Kinases
  • lyn protein-tyrosine kinase
  • src-Family Kinases
  • Proto-Oncogene Proteins c-akt
  • Cyclic AMP-Dependent Protein Kinases