Background: Intrauterine hypoxia is one of the important causes of lung dysplasia in fetal, while the mechanism has not been fully elucidated.Our laboratory found the activation of NMDA receptor play an important role in the dysplasia of fetal lung induced by intrauterine hypoxia.But whether intrauterine hypoxia has impact on postnatal lung development or NMDA receptor activation take part in this process has not been reported.Objective: To examine the protective effect by blocking NMDA receptor in the lung dysplasia induced by intrauterine hypoxia.Methods: The pregnant sprague-dawley(SD) rats were randomly divided into four groups,air-control group ,hypoxia-control group, air+memantine group, hypoxia+memantine group.The hypoxia-control group were placed in 10.5%±0.5% oxygen and the air+memantine group were injected intraperitoneally with memantine(antagonist of NMDA receptor) at 19-day gestation.Each group was treated for 2 days.On postnatal day 1, 3, 7, 14, 21, and month 1, 2, 3, record the progeny rat weight, lung weight, lung weight/rat weight rate,heart(right ventricle/left ventricle+septum)(RV/LV+S).And test the dynamic pulmonary compliance of the progeny rat at postnatal month 1, 2, 3.Results: (1) Intrauterine hypoxia for 2 days, the rat weight, lung weight, lung weight/rat weight rate of hypoxia-control group were significantly lower than the air-control group (P<0.05) from postnatal day 1 to day 21, while the RV/LV+S was significantly higher (P<0.05).From postnatal month 1 to 3, compared to the air-control group, there was no difference in progeny rat weight, lung weight, lung weight/rat weight rate in the hypoxia-control group, but the dynamic pulmonary compliance was significantly lower (P<0.05).(2) Memantine can reduce the decrease of progeny rat weight, lung weight, lung weight/rat weight rate and the increase of RV/LV+S caused by Intrauterine hypoxia.And improve the dynamic pulmonary compliance from postnatal month 1 to 3.Conclusions: Transient intrauterine hypoxia can cause postnatal pulmonary dysplasia, and the pulmonary function remains abnormal till in adult.NMDA receptor antagonist can protect the pulmonary dysplasia caused by intrauterine hypoxia, suggesting that the activation NMDA receptor plays an important role in this process.