Figure 13.

Conductance and block of hASIC1a D434N channels by guanidinium. (A) I-V relationships with NaCl replaced in part or in full by guanidinium·Cl, in the nominal absence of Ca²⁺. Currents were normalized to values obtained at V_m = −100 mV with 110 mM NaCl (I₀). (B) Chord conductance as a function of [guanidinium⁺] at constant [Na⁺] + [guanidinium⁺]. Data were fit by Eq. 3 (see Materials and methods), which yielded best-fit values of G_guan,max = 0.34 and K_guan = 3.9 mM. (A and B) Data represent means ± SEM for 6–14 measurements.