Caged agonist of P2Y1 and P2Y12 receptors for light-directed facilitation of platelet aggregation

Abstract

We have prepared a caged form (MRS2703) of a potent dual agonist of the P2Y1 and P2Y12 nucleotide receptors, 2-MeSADP, by blocking the β-phosphate group with a 1-(3,4-dimethyloxyphenyl)eth-1-yl phosphoester. Although MRS2703 is itself inactive at human P2Y1 and P2Y12 receptors expressed heterologously in 1321N1 astrocytoma cells or in washed human platelets, this derivative readily regenerates the parent agonist upon mild irradiation with long-wave UV light (360nm). The functional effect of the regenerated agonist was demonstrated by a rise in intracellular calcium mediated by either P2Y1 or P2Y12 receptors in transfected cells. Washed human platelets exposed to a solution of MRS2703 were induced to aggregate upon UV irradiation. At 1.0μM MRS2703, full aggregation was achieved within 1min of irradiation. Thus, this caged nucleotide promises to be a useful probe for potent P2Y receptor activation with light-directed spatial and temporal control.