Figure 5. Kinetics of I_bacl.

I_bacl is rapidly activated and deactivated upon membrane potential (E_m) jumps, and sustains without inactivation during hyperpolarization. A, sample voltage-step-activated currents recorded from a cultured Purkinje cell consecutively before (Basal), at the end of (Baclofen) and after (Wash) a 1 min application of 3 μm baclofen. The schematic above the left trace indicates the time course of the test potential. Dashed line, null-current level. E_K =−56.7 mV. B, I_bacl extracted as a difference between the basal and baclofen currents in A. The activation and deactivation phase of I_bacl (continuous black line) can be described by a double-exponential rise function (continuous grey line) and a double-exponential decay function (dashed grey line), respectively (see Methods for the definition of these functions). The parameters of the fitted functions are presented in Table 1.