Comparison of catalepsy induced by haloperidol and (+)-22a in C57BL/6 mice with the horizontal bar test. Separate groups of mice were injected with vehicle (Veh), or 0.01, 0.1, 1, or 10 mg/kg haloperidol (Hal), or 0.01, 0.1, 1, 10, or 30 mg/kg compound (+)-22a and evaluated for catalepsy 60 min later. N = 8–10 mice/treatment; *, p < 0.05, compared to the Veh control; V, p < 0.05, compared to all other groups.