Abstracts

RATIONALE: To study possible changes of behavior after status epilepticus (SE) induced at different stages of development. METHODS: SE was elicited by lithium-pilocarpine in Wistar rats 12,25 or 90 days old. After 2 hours of seizure activity SE was interrupted by paraldehyde. Controls received only lithium and paraldehyde. Two months later the animals were exposed to open field (three times) and to elevated plus maze. Individual groups were formed by 7-10 rats. RESULTS: In comparison with age-matched controls animals in all three age groups exhibited an increased exploratory activity (number of rearings) but locomotor activity (number of squares crossed) was increased only in the two older groups. Habituation with repeated exposures observed in all controls was present in animals undergoing SE at the age of 12 or 25 days but not in rats seized as adults. Comfort behavior (grooming) was decreased in all age groups. Increased exploratory activity was observed also in elevated plus maze whereas transfer latency to closed arms as well as time spent in the closed and open arms were not changed. CONCLUSIONS: Late behavioral consequences were found in rats undergoing SE at all three ages used, including the 12-dayold ones, i.e. a very early developmental stage. Changes in behavior varied according to the age of SE induction. Supported by a grant No.309/99/0193 of the Grant Agency of the Czech Republic.