The effect of chronic administration of sodium barbitone on chemically and electrically induced convulsions in the rat

Sodium barbitone was given to rats in increasing doses over a period of 5 weeks. The effects of a convulsant barbiturate, leptazol, and electroshock were determined at weekly intervals throughout the period of barbitone administration and at 2, 7 and 14 days following the withdrawal of the barbiturate.

There was a marked decrease in the seizure susceptibility of the experimental rats during the period of barbiturate administration. On withdrawal of the barbiturate all the experimental rats were hyperexcitable and some developed spontaneous convulsions. However, the seizure susceptibility to electroshock and to the convulsant barbiturate was no greater than that observed in the untreated animals. After the withdrawn animals had been challenged with leptazol however, the severity of the convulsions was considerably increased compared with that in the untreated animals. The seizure susceptibility of the experimental rats was the same as that of the untreated animals 14 days after the barbiturate had been withdrawn.