Effects of MAK on freezing behavior in the contextual fear-conditioning test. Results are the mean ± S.E.M. of freezing scored for a 10-min observation period. The number of rats per group was: control group, n = 9; MAK(0.3 g/kg)-treated group, n = 6; MAK (1 g/kg)-treated group, n = 8. *P < 0.05 compared with the control group, one-way analysis of variance followed by Bonferroni’s test.