| Abstract: | The electrophysiological properties of sevoflurane (Sev)-induced current (ISev) were investigated in CA1 pyramidal neurons freshly dissociated from the rat hippocampus by using the nystatin perforated patch recording configuration under voltag-clamp condition. Within the range of Sev concentrations from 3 · 10−4 to 2 · 10−3 M, Isev was an inward current which consisted of an initial transient peak component and a successive steady-state plateau component. The peak current component increased in a concentration-dependent manner with a conductance increase. The application of Sev over 2 · 10−3 M, however, suppressed the peak and steady-state current components with a concomitant decrease in conductance and elicited a transient inward current (‘hump’ current) immediately after wash out. The current-voltage relationship for ISev showed some outward rectification suggesting a slight voltage-dependency of the Isev. The reversal potential of ISev (ESev) was close to the ECl and shifted by 52 mV for a 10-fold change in extracellular Cl− concentrations, indicating that ISev is passing through Cl− channels. The single channel conductance obtained from the analysis of the variance of ISev fluctuations was 15.3 ± 1.3pS. |
