Objective: To investigate the anti-d-epressant effects of pueraria isoflavone in mice. Method: Male KM mice were randomly divided into 5 groups:control groups (normal saline)

fluoxetine group (10 mg ·kg-1)

pueraria isoflavone groups (50

100

200 mg·kg-1). After oral administration for 14 days

the open field test (OFT)

forced swimming test (FST)

tail suspension test (TST)

5-Hydroxytryptophan (5-HTP)-induced head-twitch test and reserpine-antagonism test were carried out to evaluate the anti-depressant effects of pueraria isoflavone. In particular

reserpine (2 mg·kg-1) and 5-HTP (150 mg·kg-1) were given by intrapertioneal injections before the reserpine-antagonism test and 5-HTP-induced head-twitch test respectively. Result: The number of wearing and grooming in 2 min in control mice were (57.23±18.35) and (22.16±13.28) respectively

and there was no significant different between pueraria isoflavone groups and control group. The immobility time of FST and TST in control mice was (132.7±37)

(98.4±28 ) s respectively and there were significant decrease in pueraria isoflavone groups. pueraria isoflavone at dose of 100 mg·kg-1could short immobility time to (72.1±27)

(68.8±19) s. Moreover

pueraria isoflavone enhanced the head-twitch respone evoked by 5-HTP in dose-dependent manner (P<0.001). Compared with model group

pueraria isoflavone could significantly reverse the ptosis

acinesia

and decrease in body temperature induced by reserpine in mice (P<0.05). Conclusion: Pueraria isoflavone has anti-depressant effects

and its mechanism may be related to regulating the functions of monoaminergic nervous system.