Evidence for the involvement of nigral GABAB receptors in seizures of rat pups.

The substantia nigra GABA-sensitive system is important for the modification of seizures. In adult rats, nigral infusions of baclofen (GABAB agonist) had no effect on flurothyl seizures. This suggests that the nigral GABAB receptor system may not be involved in the mediation of flurothyl seizures in this age group. The present study examines whether the nigral GABAB receptor is involved in the modification of flurothyl seizures in rat pups and whether systemic infusions of baclofen could alter their seizure susceptibility. Baclofen (50-200 ng/0.25 microliters) was intranigrally administered to 16-day-old rat pups which were then exposed to flurothyl seizures. Results indicated that intranigral infusions of baclofen (100 and 200 ng/0.25 microliters) protected the rat pups against seizures. Systemic injections of baclofen also protected pups from flurothyl seizures suggesting that it may be worthwhile to examine baclofen as a potential antiepileptic drug in children.