Figure 4.

The C1 F87Y substitution abolished the biphasic nature of concentration-response relationship. A, examples of currents mediated by GABA_AR β₃ C1 F87Y, evoked by increasing concentrations of GABA. B, concentration-response relationship obtained using the percentage of the maximum amplitude recorded for each cell. The inhibition caused by 100 mm GABA in β₃ C1 was abolished by the F87Y substitution. A summary of the data is in Table 2. C, mean 10–90% rise times showed no significant change with increasing GABA concentrations in β₃ C1 F87Y except comparing 100 with 1 mm (p = 0.008, n = 4, F(4,15) = 5.2, one-way ANOVA post hoc Dunnett's). D, mean deactivation weighted τ was also independent of GABA concentrations (p = 0.5, one-way ANOVA, F(4,15) = 0.96). Detailed information about the components is in Table 3. Error bars represent S.D.