AIM: To investigate the effects of the water extracts of Danggui Shaoyao San (DGSYS) in rats used the passive avoidance task. METHODS: Impairment in learning acquisition in rats was induced by colchicines, and the level of superoxide dismutase in the brain and the effects of DGSYS on the locomotor activity and pain threshold induced by colchicines, were detected. RESULTS: DGSYS (0.1 - 1.0 g/kg) attenuated the impairment of learning acquisition induced by colchicine (15 mug) and DGSYS (0.5 and 1.0 g/kg) increased the level of SOD (141 +/- 3 and 135.4 +/- 2.0) in the brain. However, DGSYS (0.1 - 1.0 g/kg) did not affect the locomotor activity and pain threshold in the rats treated with colchicines. CONCLUSION: DGSYS can improve the learning acquisition deficit induced by colchicine in rats. The action mechanism of DGSYS may be involved in the increase in the level of super-oxide dismutase.
