Larger Image Figure 5. The two-α and three-α form of the α3β4 receptor differ in their response to Zn2+ modulation.Traces in (A) are typical currents activated by an EC20 concentration of ACh on the two-α receptor (left, 1∶9 α∶β ratio) and the three-α receptor (right, 9∶1 ratio) in the presence of increasing concentrations of Zn2+. Zn2+ was pre-applied to oocytes for 30 s before it was applied together with ACh. (B) Zn2+ concentration-response curves for the three-α receptor (filled squares) and the two-α receptor (filled circles). Curves from different cells were pooled and fitted to the Hill equation and to the sum of two Hill equations, respectively. Note that Zn2+ potentiated only the ACh responses of oocytes expressing the two-α stoichiometry. Image published in: Krashia P et al. (2010) Krashia et al. Creative Commons Attribution license Permanent Image Page Printer Friendly View XB-IMG-125399 |