Figure 5.

Clustering increases deactivation rate. The cell was held at −60 mV, and the dashed line indicates zero current level. GABA (5 μM) induced an inward current. When GABA was rapidly removed, the current gradually decreased to zero. The deactivation phase of currents was best fit with a single exponential. Diffuse receptors had an average time constant τ = 117 ± 10.5 ms (mean ± SE, n = 6); clustered receptors' deactivation rate was faster, with time constant shorter, τ = 51 ± 4 ms (mean ± SE, n = 3). The difference is statistically significant (P < 0.05, t test).