Objective      To evaluate the effect of cadmium exposure in the early period after birth on physiological and neurobehavioral changes in newborn mice  and explore the related mechanism.      Methods        Newborn ICR mice were randomly divided into 4 groups

with 10 mice in each group. The 4 groups were injected intraperitoneally with cadmium chloride at 2.0

1.0

0.5 and 0 mg/kg

respectively

every other day from postnatal day (PND) 3 to PND 13. Some mice were killed at 24 h after the last exposure to measure MDA and GSH levels in the brain and observe the brain neuropathological changes. The rest mice were fed until PND 35

and the neuropathological tests were performed. The organs including the brains

liver

lungs

kidneys

uterus and testes were taken out and weighed. Brain slices were stained with HE to examine the brain neuropathological changes.      Results       MDA level was significantly higher in the 2.0 mg/kg group and 1.0 mg/kg group (P0.05)

and the activity of GSH in 2.0 mg/kg group was lower than that of the other groups (P0.05). The eye opening time in 2.0 mg/kg group and 1.0 mg/kg group was delayed (P0.05). The sensorimotor abilities including cliff aversion and open field traversal were affected in the exposure groups (P0.05). The neuropathological test showed that the cerebral cortex cells were more loose in the 2.0 mg/kg group than those in the control group.      Conclusion       Cadmium exposure in the early period after birth induces physiological and neurobehavioral changes in mice.