Figure 3.
The peak GABA current amplitudes were reduced, but the kinetic properties were not altered for α4β2δ receptors containing mixed wild-type and variant or pure variant δ(R220H) receptors. A, Representative whole-cell current traces evoked by saturating GABA (1 mm) from wild-type α4β2δ, mixed wild-type and variant, and pure variant α4β2δ(R220H) receptors. B, Compared with wild-type receptors (n = 77), the mean current amplitude was smaller for the mixed receptors (n = 20) as well as for pure variant receptors (n = 24). C, The mean extent of desensitization was not different among wild-type, mixed, and pure variant receptors. D, The mean rate of current deactivation of mixed, and pure variant receptors was not altered compared with wild-type receptors. The solid bar above each current trace denotes the duration of GABA application (4 s). The open bars represent the mean current features for wild-type receptors, the hatched bars represent those for the mixed receptors, and the black bars represent those for pure variant receptors. wt, Wild-type α4β2δ receptors; mix, presence of both receptors; var, pure variant receptors. The error bars denote SEM. The asterisks indicate significant difference from wild-type α4β2δ receptors (**p < 0.01).