Prenatal Topiramate Exposure Induced Developmental Changes in Rat Brain

Female Charles Foster pregnant rats were treated with Topiramate which is a newer antiepileptic drug used in refractory partial seizure. The drug was introduced through oral route in the doses of 40, 100 and 200 mg/kg body weight from days 9–12 of gestation (Sperm +ve = 0 day) in female rats. Control female rats were introduced equivalent amount of tap water through the same route. The fetuses from both control and treated groups were collected on day 21 of gestation after sacrificing the mothers by deep ether anaesthesia. They were examined, weighed and further fixed in formalin for histomorphological examination. The brains were dissected out, on gross examination, they did not show any difference in morphology between control and treated groups. Histological observation of the treated brains showed dilatation of blood vessels and spongiform changes disturbing typical laminar pattern of the cortical plate in cerebrum and scattered patches of gliosis around degenerated cellular mass. The subventricular zone was found to be thickened in comparison to the control brains. The changes were similar in all three treated groups as compared to the controls except that the severity of drug insult increased with increasing doses of the drug. doi: 10.5214/ans.0972.7531.2005.120204