Effects of carbamazepine on bicuculline- and pentylenetetrazol-induced seizures in developing rats.

The anticonvulsant effect of carbamazepine (CBZ) was examined in 10-, 18- and 25-day-old Wistar albino rats into which bicuculline or pentylenetetrazol had been systemically injected to induce generalized epileptic manifestations typical for the specific age of the animals. The results showed that: a) in developing rats, CBZ appears to be more effective in the pentylenetetrazol than the bicuculline model of epilepsy; b) in both models of epilepsy the efficacy of CBZ increases with the age of the animals; and c) among the various epileptic manifestations, the tonic phase is the most sensitive to the anticonvulsant effect of CBZ. These conclusions are correlated with the different levels of cerebral maturation of the animals, and are discussed with reference to the mechanisms of action of CBZ and bicuculline or pentylenetetrazol.