Figure 2.

(A) Plot of measured initial reaction rates (represented in nM min⁻¹ per nM enzyme, or min⁻¹, at 37 °C, measured in triplicate, with error bars in standard deviations) versus the substrate (heroin) concentration for recombinant human BChE-catalyzed hydrolysis of heroin. (B) Locomotor activity in mice expressed as total distance traveled (in centimeters) per min after heroin injection (2.5 mg/kg, IP) or saline, with or without ethopropazine injection (10 mg/kg, IV) 10 min prior to the heroin (or nothing) injection (2.5 mg/kg, IP) at the time 0. A group of eight mice (n = 8) were used at the same time for each dose condition.