Deactivation and desensitization kinetics.A, GABA (1 mm) was applied for 1 msec to a basket cell nucleated patch. The current decay (τtotal) could be described by the sum of two exponentials termed τ1 and τ2, as shown in the bottom pannel of A. The open tip response is displayed above the current traces in this and all other figures. B, Application of 1 mm GABA for 100 msec to the same patch resulted in a current flow with similar amplitude, rise time, and decay time constants. C, The recovery from desensitization was studied with a protocol of two 1 msec pulses of 1 mm GABA with variable interpulse intervals. The extent of recovery from desensitization was obtained from the amplitude ratio of the second pulse divided by the first (I2/I1). The current amplitudes were both measured from the baseline directly before the corresponding agonist application (shown in theinset). The ratios obtained from eight nucleated patches were plotted semilogarithmically against the interpulse interval and fitted with a biexponential function.
