Adenosine 5'-(tetrahydrogen triphosphate), 2-chloro-, sodium salt (1:4)

2-Chloroadenosine 5-triphosphate (2-chloro ATP) is an adenine nucleotide and analog of ATP .1,2 It is an antagonist of the purinergic P2Y1 receptor, inhibiting intracellular calcium mobilization induced by ADP in Jurkat cells expressing the human receptor (Ki = 2.3 μM).3 2-chloro ATP is an agonist of purinergic P2X receptors, inducing inward currents in HEK293 cells expressing the human bladder smooth muscle or rat PC12 forms of the receptor (EC50s = 0.5 and 2.5 μM, respectively).4 It induces relaxation of precontracted isolated guinea pig taenia caeci strips in a concentration-dependent manner.1 It has been used to study the substrate specificity of cyclic nucleotide-dependent protein kinases, such as protein kinase A (PKA) and PKG.2

1.Satchell, G., and Maguire, M.H.Inhibitory effects of adenine nucleotide analogs on the isolated guinea-pig taenia coliJ. Pharmacol. Exp. Ther.195(3)540-548(1975) 2.Flockhart, D.A., Freist, W., Hoppe, J.O., et al.ATP analog specificity of CAMP-dependent protein kinase, cGMP-dependent protein kinase, and phosphorylase kinaseEur. J. Biochem.140(2)289-295(1984) 3.Hechler, B., Vigne, P., Léon, C., et al.ATP derivatives are antagonists of the P2Y1 receptor: Similarities to the platelet ADP receptorMol. Pharmacol.53(4)727-733(1997) 4.Evans, R.J., Lewis, C., Buell, G., et al.Pharmacological characterization of heterologously expressed ATP-gated cation channels (P2x purinoceptors)Mol. Pharmacol.48(2)178-183(1995)