Abstracts

Animal models of chronic epilepsy with spontaneous seizures may be useful for antiepileptic (AED) drug development. Convenient and effective methods for testing potential AEDs over days and weeks should facilitate many experiments. This study investigated the effect of carbamazepine (CBZ) administered in food pellets on rats with kainate-induced epilepsy., Adult male rats (Sprague-Dawley; 150-250 g) were given repeated low-dose kainate treatment (5 mg/kg ip hourly until convulsive status epilepticus persisted [gt]3 h). Food pellets with CBZ were provided (30, 100 or 300 mg/kg/day) in three 2-week trials (n = 7[ndash]9 rats) involving 5 days of CBZ or control treatment, separated by 2 recovery days. The total amount of food provided corresponded to normal caloric diet of 60 gm/kg/day., All animals consumed the entire daily drug-in-food dose intermittently but continuously throughout the 24-h day. CBZ significantly reduced mean seizure frequency in a dose-dependent manner. At 30 and 100 mg/kg/day, CBZ treatment consistently failed to block all motor seizures, but no [italic]motor seizures[/italic] were observed in any of the rats at 300 mg/kg/day., This AED-in-food protocol appears to be an effective means of chronic drug administration. When administered over 5-day periods, CBZ reduced the frequency of spontaneous motor seizures in a dose-dependent manner, but very high doses were required to block all motor seizures. The effects on electrographic seizures remain to be determined., (Supported by NS 049620 (FED).)