Fig. 2. Effect of isoflurane and halothane on 2,4-dinitrophenol (DNP)-activated IKATP. Current was monitored every 15 s during a 100-ms test pulse to 0 mV from a holding potential of −40 mV. Traces are sequentially shown at the time depicted. The time t = 0 min denotes current recordings in control obtained immediately prior to application of DNP. The effects of 1.3 mm isoflurane (top ) and 0.4 mm halothane (bottom ) are shown. Isoflurane and halothane were applied after steady state effects of DNP were reached. Note that the holding current at −40 mV was increased due to activation of IKATPby DNP and by DNP + isoflurane. In contrast, the holding current was depressed by DNP + halothane.