Fig. 7. The effect of ethanol on oxygen consumption in isolated brown adipocytes. (A ) The effect of ethanol on the dose-response curve for norepinephrine-induced oxygen consumption. The experiments were performed as in fig. 1C, but with 390 mm ethanol added. Curves were drawn for simple Michaelis-Menten kinetics with defined V^max(the response to 1 μm norepinephrine for controls and to 10 μm for ethanol-treated cells). (B ) Basal (open circles) and maximal norepinephrine-induced (closed circles) rates of oxygen consumption in different ethanol concentrations. (C ) EC⁵⁰for norepinephrine, as an effect of different ethanol concentrations. The curve was drawn for best fit to the equation IC⁵⁰(ethanol) = EC⁵⁰· (1 +[ethanol]/K^B); K^Bwas thus calculated to be 50 mm ethanol. The values are the means from experiments in two different cell preparations.