Benzoyl ATP is an antagonist of rat and human P2Y1 receptors and of platelet aggregation

Biochem Biophys Res Commun. 1999 Mar 5;256(1):94-7. doi: 10.1006/bbrc.1999.9558.

Abstract

The effects of 2'- and 3'-O-(4-benzoylbenzoyl)-ATP (BzATP) on intracellular Ca2+ mobilization and cyclic AMP accumulation were investigated using rat brain capillary endothelial cells which express an endogenous P2Y1 receptor, human platelets which are known to express a P2Y1 receptor, and Jurkat cells stably transfected with the human P2Y1 receptor. In endothelial cells, BzATP was a competitive inhibitor of 2-methylthio ADP (2-MeSADP) and ADP induced [Ca2+]i responses (Ki = 4.7 microM) and reversed the inhibition by ADP of adenylyl cyclase (Ki = 13 microM). In human platelets, BzATP inhibited ADP-induced aggregation (Ki = 5 microM), mobilization of intracellular Ca2+ stores (Ki = 6.3 microM), and inhibition of adenylyl cyclase. In P2Y1-Jurkat cells, BzATP inhibited ADP and 2-MeSADP-induced [Ca2+]i responses (Ki = 2.5 microM). It was concluded that BzATP is an antagonist of rat and human P2Y1 receptors and of platelet aggregation. In contrast to other P2Y1 receptor antagonists (A2P5P and A3P5P) which inhibit only ADP-induced Ca2+ mobilization, BzATP inhibits both the Ca2+- and the cAMP-dependent intracellular signaling pathways of ADP. These results provide further evidence that P2Y1 receptors contribute to platelet ADP responses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Diphosphate / analogs & derivatives
  • Adenosine Diphosphate / antagonists & inhibitors
  • Adenosine Diphosphate / pharmacology
  • Adenosine Triphosphate / analogs & derivatives*
  • Adenosine Triphosphate / pharmacology
  • Adenylyl Cyclase Inhibitors
  • Adenylyl Cyclases / metabolism
  • Alprostadil / pharmacology
  • Animals
  • Blood Platelets / drug effects
  • Blood Platelets / physiology
  • Brain / blood supply
  • Calcium / metabolism
  • Cholera Toxin / pharmacology
  • Cyclic AMP / pharmacology
  • Endothelium, Vascular / cytology
  • Endothelium, Vascular / drug effects
  • Humans
  • Inhibitory Concentration 50
  • Jurkat Cells
  • Platelet Aggregation / drug effects*
  • Platelet Aggregation Inhibitors / pharmacology*
  • Purinergic P2 Receptor Antagonists*
  • Rats
  • Receptors, Purinergic P2 / metabolism
  • Receptors, Purinergic P2 / physiology
  • Receptors, Purinergic P2Y1
  • Signal Transduction / drug effects
  • Thionucleotides / antagonists & inhibitors
  • Thionucleotides / pharmacology
  • Transfection

Substances

  • Adenylyl Cyclase Inhibitors
  • P2RY1 protein, human
  • P2ry1 protein, rat
  • Platelet Aggregation Inhibitors
  • Purinergic P2 Receptor Antagonists
  • Receptors, Purinergic P2
  • Receptors, Purinergic P2Y1
  • Thionucleotides
  • methylthio-ADP
  • adenosine 5'-O-(3-thiotriphosphate)
  • 3'-O-(4-benzoyl)benzoyladenosine 5'-triphosphate
  • Adenosine Diphosphate
  • Adenosine Triphosphate
  • Cholera Toxin
  • Cyclic AMP
  • Adenylyl Cyclases
  • Alprostadil
  • Calcium