Fig 4. ACh concentration-response relations for α5α4β2 and α5α4β2V287L nAChRs.

The α5α4β2 and α5α4β2V287L receptors were expressed in Xenopus oocytes using a large excess of α5 mRNA (α5:α4:β2 mRNA injection ratio of 10:1:1 w/w/w) to ensure that α5-containing (α5*) nAChRs were the predominantly expressed subtype. a-b. Voltage-clamped ACh responses of oocytes expressing α5α4β2 (a) or α5α4β2V287L receptors (b). c. Normalized ACh concentration-relations for the WT α5α4β2 (filled circles), and mutant α5α4β2V287L (open circles), nAChRs superimpose. The lines are fits to a single hyperbolic binding component using non-linear least-squares regression. The data for both receptors were normalized to the fitted maximum response to facilitate comparison of their ACh sensitivities. Symbols are the means of 4–8 oocytes. Holding potential = -60 mV.