Fig. 2. Specificity of P2X primer and probe sets and standard curve analysis. (A) Real-time PCR amplification plot showing specificity of P2X receptor primer/probe sets with their target templates. Seven successful amplifications are shown, with absence of amplification of mismatched templates (see B). (B) Grid representation of primer and probe specificity showing C_T values for on-target cDNA amplification for all seven P2X receptors. Note the absence of non-specific amplification. (C) An example of a standard curve for P2X₁ receptor cDNA amplification. Note the linearity to <10 copies. (D) Standard curve analysis of the P2X receptor targets showing linearity of all seven dilution series. GAPDH, glyceraldehyde-3-phosphate dehydrogenase; NSE, neuron-specific enolase. Copy range used for the standard curves is estimated from the serial dilutions of template cDNAs.