Abstract: ObjectiveTo investigate the protective effects and possible mechanisms of polydatin on the expression of brain-derived neurotrophic factor(BDNF)in cortex of neonatal rats with hypoxic-ischemic brain damage(HIBD).MethodsFifty-two neonatal SD rats were divided randomly into normal sham-operated(NS),negative control(NG),HIBD(HI), and polydatin treatment group(PD).The HIBD model was established in 7 days old rats by left carotid artery ligation and 2 hours hypoxia.Two subgroups were individed according to the model after 24 hours and 10 days.Immunohistochemistry was used to measure the expression of BDNF in cortex.ResultsThe results of immunohistochemistry demonstrated that the expressions of BDNF in cortex in HI groups at 24 hours and 10 days(0.144±0.011,0.105±0.011)were significantly higher than those in NS group(0.069±0.005,0.068±0.005)and NG group(0.070±0.003,0.069±0.007)(P<0.01 for all);the expression of BDNF in cortex in PD group(0.131±0.009)was significantly higher than that in HI group (0.105±0.011)(P<0.01).ConclusionPolydatin had possible neuroprotection effect in hypoxic-ischemia brain injury and the mechanism was probably related to the upregulation of the expression of BDNF in cortex in neonatal rats.