Abstract: Objective:To explore the expression and significance of Caspase-3 in mouse with embryonic neural tube defects(NTD) induced by retinoic acid(RA).Methods:The 40 mice were randomly divided into test and control groups.The neural tubal samples were harvested at 18,42,66 and 90 h after RA or arachis oil administration.Western blotting was used to detect the expression of Caspase-3.Results:The expression of Caspase-3 displayed time dependence in the normal fetal neural tube tissue.In control group,the expression level of Caspase-3 increased at 18 h,and achieved the most peak at 42 and 66 h,then decreased slowly after arachis oil administration.In test group,the expression levels of Caspase-3 were significant lower than that of control group at 42 h(P0.01),and significant higher than that of normal group at 66 h and 90 h after treatment with RA(P0.01).Conclusions:RA can change the expression pattern of Caspase-3 in embryonic neural tube of mouse,The Caspase-3 alteration may participate in the formation of NTD induced by RA.