a The schedule of the test. On day 1, mice were subjected for pre-test. On day 2–7, mice were injected with saline or various doses of b SLL-039 (−2 h), c SLL-1206 (−3 h) or U50,488H (−15 min) before each 30-min conditioning. On day 8, the time spending in each side was recorded and the CPA score was calculated. Data were analyzed by one-way ANOVA followed by Bonferroni post hoc test. Value data were presented as mean ± SEM from at least ten mice. **P < 0.01 vs saline