The P2X receptors belong to the ligand-gated ion channel family and are activated by extracellular ATP.The P2X2 receptor subtypes has a widespread tissue distribution in autonomic neurons, but it is generally found to be co-expressed with one or more subtypes.mRNA of the P2X1, P2X2, P2X3, and P2X6 receptors is found in neurons of dorsal root ganglia (DRG), trigeminal, and nodose ganglia where heteromeric P2X2/P2X3 receptors are found
