FETAL RAPHE TRANSPLANTS REDUCE SEIZURE SEVERITY IN SEROTONIN-DEPLETEDGEPRS

THIS study investigated whether transplantation of fetal raphe tissue into genetically epilepsy-prone rats (GEPR-3s) would reduce the severi ty of seizures previously exacerbated by depletion of brain serotonin. Mild-seizure GEPR-3s were depleted of brain serotonin by 5,7-dihydrox ytryptamine (DHT) and evaluated for seizure severity. Rats then receiv ed 15-day fetal raphe tissue, fetal neocortical tissue or were sham gr afted. GEPR-3s treated with 5,7-DHT showed increased seizure severity following depletion of serotonin and subsequent reductions in severity as a result of fetal raphe transplantation. Sham- or neocortex-grafte d rats maintained elevated seizure severity scores throughout the stud y. Prominent raphe or cortical grafts were observed within the third v entricle of GEPRs at autopsy. These findings show that transplantation of fetal raphe tissue promotes lasting reductions in increased seizur e severity resulting from depletion of serotonin in the GEPR brain.