Efficacy for Reduction of Depression Behavior in Mice—Sucrose Splash. (A,B) Comparisons for three of the CCK-BR scFvs were tested for effects on depression measures typically associated with chronic pain in male mice. The scFvs 14-3 improved the total grooming time, but no variant had an effect on the number of times groomed. (C,D) Dose comparisons for the 77-2 CCK-BR scFv were tested for effects on depression measures typically associated with chronic pain in male mice. The 0.4, 4.0, and 40 mg/kg doses were efficacious in improving the number of times groomed compared to vehicle treatment and grooming time. (E,F) In female mice, treatment with the 77-2 scFv improved the number of times groomed and the total grooming time. * p<0.05, ** p < 0.01, *** p < 0.001, 2-way ANOVA.