Fig. 3. The current–voltage relation for adenosine triphosphate–sensitive potassium channels during (A ) control conditions and (B ) after the application of propofol (16.7 μg/ml). The propofol concentration presented is the actual concentration measured in the current study. The curve is linear in the negative membrane potential range but shows rectification with depolarization beyond zero. Each data point (vertical bars) is presented as the mean ± SD.