Studies on the intracerebral metabolism of anticonvulsant drugs--II. Disposition of carbamazepine in the isolated perfused rat brain.

ABSTRACT

Carbamazepine (CBZ) was perfused (85 nmoles/ml) through the isolated brains of rats. After 2 hr the mean regional concentrations of the drug were between 170 and 234 nmoles/g wet weight. The total brain content of CBZ was 390 nmoles. During perfusion 82 nmoles epoxycarbamazepine (E-CBZ) were formed, most of which were found in perfusion medium. Tissue levels of E-CBZ were between 0.3 and 2.8 nmoles/g wet weight. No dihydroxycarbamazepine (DH-CBZ) could be found. Pretreatment of the rats with phenobarbital neither influenced the uptake of CBZ into the brains nor increased the formation of E-CBZ significantly.