Teratogenic effects of phenytoin on the development of skeleton and neural tube of mouse fetuses

Phenytoin is one of the oldest anti epileptic drugs; it may result in fetal abnormalities if taken during pregnancy. This study was designed to determine teratogenic effects of phenytoin on the development of skeleton and neural tube defects in mouse fetuses.. Forty small experimental pregnant mice (NMRI Type) were divided in to three experimental groups (I, II, III) and one control group. The experimental groups received phenytoin in doses of 60, 75 and 90 mg/kg/day and the control group received 0.2 ml normal saline intraperitoneally (ip) from the 6th day to 14th day of pregnancy. The mice were sacrificed on the 18th day of pregnancy and fetuses examined for skeletal abnormality. Alizarin red and Alcian blue stains were used to detect neural tube abnormalities. Data was analyzed with ANOVA and Tukey tests. In all three experimental groups (I-III) abnormalities were observed in the skeletal system, abnormalities primarily consisted of displacement and disruption in the shape of the limbs, rate of these anomalies was significantly different from the control group (p<0.05); also the rate of neural tube defects as spina bifida cystica was significantly higher in experimental group III as compared to the control group, (p<0.05). Findings of this study show that ingestion of phenytoin during pregnancy can induce neural tube defects and skeletal abnormalities in the mouse fetus.. Keywords: phenytoin, teratogen, neural tube defects, skeletal abnormalities.