HUMAN BRAIN SODIUM-CHANNELS AS ONE OF THE MOLECULAR TARGET SITES FOR THE NEW INTRAVENOUS ANESTHETIC PROPOFOL (2,6-DIISOPROPYLPHENOL)

Single sodium channels from human brain cortex tissue were incorporated into voltage-clamped planar lipid bilayers in the presence of batrachotoxin and studied with various doses of the new anaesthetic compound propofol (2,6-diisopropylphenol). Propofol was found to depress two major sodium channel functions, leading to a reduction of the time-averaged fractional channel open-time (half-maximal blocking concentration, ED50, 20-mu-M; maximal block 28%) and an interaction with the steady-state activation. These effects occurred at clinically relevant serum concentrations, suggesting the human brain sodium channel as one of the molecular target sites of action for propofol.