Figure 6. A plot of the amplitude of the fast fluorescence decay as a function of Dns-C^6-Choconcentration in the presence of 1.5 mM isoflurane. The curve is a fit to Equation 2, yielding a dissociation constant (K^d) of 1.2 +/− 0.2 [micro sign]M and a Hill coefficient of 1.8 +/− 0.4. The K^dis not different from that measured in the absence of anesthetic. [28]The nicotinic acetylcholine receptor concentration during the preincubation period was 0.2 [micro sign]M. Data points on all figures represent the mean of two separate experiments, and the error bars indicate the range of the data.