Figure 2. Both volatile anesthetics and nonanesthetics inhibit wild-type nicotinic acetylcholine receptor (nAChR) currents. Examples of ensemble currents from three different oocyte patches expressing wild-type nAChRs are shown. Each panel shows an ensemble average (8–16 events) current elicited with 200 [micro sign]M acetylcholine and another ensemble average current from the same patch in the presence of the indicated concentration of volatile inhibitor. Enflurane-inhibited currents maintain a single exponential decay phase (desensitization), whereas currents inhibited by F6 and F8 show two current inhibition phases. The rapid decay phase indicates state-selective inhibition of nAChR in the open channel state. Decay phases of the currents were fitted with Equation 1or Equation 2as described in Materials and Methods. Table 1summarizes kinetic fit results.