Effects of intravenous saline, naltrexone, and nalmefene on adrenocorticotropic hormone (ACTH), in male and female volunteers. Data (n = 16) are presented as mean ± standard error of the mean. Time course data (a): A two-way repeated measures ANOVA was significant for treatment day, F(2, 30) = 14.12, p < .001, and time, F(12, 180) = 4.25, p < .001, main effects, and for their interaction, F(24, 360) = 5.19, p < .001. Area under the curve (AUC) data for the period 0 to 180 min (b): A one-way repeated measures ANOVA was significant for treatment day, F(2, 30) = 12.33, p < .001. Black lines in panel (b) show significant Tukey post hoc tests.