Fig. 1.

Recombinant Gβ₂γ₂, but not Gβ₁γ₂, inhibits α_1H channel activity in patches excised from HEK-293 cells. (A and B) Shown are records and analysis of single-channel I_Ca currents elicited by repeated (6-sec) test pulses to −35 mV from −90 mV. Five consecutive sweeps and the ensemble average of 105 sweeps concatenated from three cells (bottom trace) recorded before (Left) and after (Right) reconstitution of 1 nM Gβ₂γ₂ (A) or Gβ₁γ₂ (B) into the patch. (C) Time course of NP_o from two representative patches before and after adding Gβγ. Sequential exposure to vehicle (sweeps 1–50) and in sweeps 51–100 Gβγ dimer: Gβ₂γ₂ (Left) or Gβ₁γ₂ (Right). Blank/inactive sweeps (Nulls) are indicated by filled circles arbitrarily drawn at 0.3 (NP_o) for clarity. (D) Bar graphs plot mean ± SEM of the percent reduction in NP_o (Left) or percent increase in nulls (Right) elicited by Gβ₂γ₂ or Gβ₁γ₂ relative to vehicle exposure for each patch_. Numbers are patches recorded for each condition. ∗, P < 0.05 compares vehicle with treatment groups by ANOVA.