The course of untreated seizures in the pilocarpine model of epilepsy

The course of untreated epilepsy is not well. established. This study uses a model of chronic limbic epilepsy (pilocarpine model of epilepsy) to deter mine the pattern of occurrence of seizures in untreated animals. Following pilocarpine administration, 21 rats were monitored continuously with a vide o system for 135 days after the first spontaneous seizure. Animals showed a great variability in seizure numbers and were divided in two subgroups pre senting either a low frequency of seizures (n = 9 animals presenting ten or less seizures in the first 15 days of observation) or a high frequency of seizures (n = 12 animals presenting more than ten seizures during this peri od). Animals with low number of seizures during the first 15 days of observ ation showed a significant increase in seizure frequency in the following p eriod of analysis (until 105 days). On the other hand, those with initial h igh number of seizures showed Significant changes in seizure frequency only in the first 2 months. The duration of each spontaneous seizure did not ch ange significantly over time. These findings show that in untreated epileps y there is a maturation process in the early stages and this accelerating p rocess can be of predictive value for the treatment of epilepsy. (C) 1999 E lsevier Science B.V. All rights reserved.