2-Chloroadenosine 5-triphosphate (sodium salt) (Synonyms: 2-chloro ATP)

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 (K_i = 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)