Figure 3.

Potency of α-Ctx PeIA on α6/α3β4 nAChRs formed by switching species subunits. Different combinations of H and R α6/α3 and β4 subunits were expressed in X. laevis oocytes and subjected to TEVC electrophysiology as described under “Experimental procedures.” A–C, inhibition curves for ACh-evoked currents by PeIA, PnIA, and TxIB were obtained from oocytes expressing human α6/α3 with rat β4 subunits (closed circles) or rat α6/α3 with human β4 subunits (open circles). Data for inhibition of human (dashed red) and rat (dashed green) α6/α3β4 nAChRs by PeIA, PnIA, and TxIB were previously presented and shown for ease of comparison. Values are provided in Table 2. Error bars, S.D. from at least four oocytes for each IC₅₀ determination.