Sevoflurane-induced ionic current in acutely dissociated CA1 pyramidal neurons of the rat hippocampus.
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 voltage-clamp condition. Within the range of Sev concentrations from 3 x 10(-4) to 2 x 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 x 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 +/- 1.3 pS.
Wu
J
J
Department of Neurophysiology, Tohoku University School of Medicine, Sendai, Japan.
Harata
N
N
Akaike
N
N
D000818:Animals; D002712:Chlorides / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004553:Electric Conductivity; D004560:Electricity; D004594:Electrophysiology; D004987:Ethers / Q000494:pharmacology*; D005110:Extracellular Space / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D007477:Ions; D008738:Methyl Ethers; D009994:Osmolar Concentration; D017966:Pyramidal Cells / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D000077149:Sevoflurane
D002712:Chlorides; D004987:Ethers; D007477:Ions; D008738:Methyl Ethers; D000077149:Sevoflurane