Abstracts

RATIONALE: Kainic acid, when it was applied locally into the sensorimotor cortex, produces focal cortical seizure status. Anticonvulsant property of the Nefiracetam was evaluated using this rat model
METHODS: Thirty five Wistar rats were used in this study. A stereotaxic operation was performed and a cannula was placed in the left sensori-motor cortex. Additionally, screw electrodes were placed for the EEG study. Exp. I: After induction of focal cortical seizure status by an intracortical injection of kainic acid(2 micrograms), 7 rats were studied behavioral change and EEG using video-EEG monitoring system. Nefiracetam(100 mg/kg) was injected intravenously from a tail vein in 7 rats. Exp. II: 14 rats were studied by LCGU(14C-deoxyglucose autoradiography) study after induction of the focal cortical seizure status. In 7 rats, Nefiracetam(100 mg/kg) was injected by way of a tail vein. For control study, after induction of the focal cortical seizure status, physiological saline was injected in 7 rats from the tail vein and processed for the autoradiogram.
RESULTS: : Exp I: Behavioral and EEG seizures were remarkably suppressed immediately after the intravenous administration of the Nefiracetam. Exp. II: Remarkable increase of LCGU was observed in the cortex, basal ganglia and thalamus on the focus side. However, hypermetabolic area was remarkably reduced after administration of Nefiracetam.
CONCLUSIONS: The present study demonstrated that remarkable anticonvulsant effect on the focal cortical seizures in rats. The result suggests that inhibition of the seizure propagation from the epileptic focus during the focal seizure status is an important role of Nefiracetam
Support: The present research was partly supported by the Daiichi Pharmaceutical Co. Ltd., Tokyo, Japan.