The Influence of Bicuculline‐Induced Seizures on Free Fatty Acid Concentrations in Cerebral Cortex, Hippocampus, and Cerebellum

Abstract

In ventilated rats maintained on N2O-O2 (70:30, vol/vol) continuous seizrues were induced with i.v. bicuculline, and free fatty acids (FFA) in cerebral cortex, hippocampus and cerebellum were analyzed after seizure durations of 1-120 min. In the cerebral cortex, peak FFA concentrations were observed after 5 min, with a 3-fold increase in total FFA content. The values then remained unchanged for the next 15-20 min but decreased thereafter. At 60 and 120 min, total FFA contents were only moderatly increased above control. In the initial period, arachidonic acid increased .apprx. 10-fold and stearic acid 2- to 3-fold, with little change in palmitic acid and linoleic acid concentrations. At all times, the docosahexenoic acid concentration was markedly increased. Following its massive accumulation at 1 min, arachidonic acid gradually decreased in concentration. Pretreatment of animals with indomethacin did not alter this behavior. After 20 and 120 min of seizure activity, changes in total and individual FFA concentrations in the hippocampus were similar to those observed in the cerebral cortex. The cerebellum behaved differently. At 20 min the only significant change was a 5- to 10-fold increase in arachidonic acid concentration, and after 120 min total and individual FFA concentrations were similar to control values. Since the control values for arachidonic acid were much lower in the cerebellum, the 20-min values were only .apprx. 20% of those observed in the cerebral cortex and the hippocampus.