The Influence of Serotonin on Seizure Susceptibility in the Gerbil
5-hydroxytryptophan (5-HTP) (50 mg/kg, I.P.) increased central serotonin (5-HT) levels and delayed the onset of seizure during reflow in gerbils subjected to transient bilateral blockade with dimethyl tryptamine (DMT) (10 mg/kg I.P.) caused early onset of seizure. Results support an influence of 5-HT on seizure threshold in the central nervous system of the gerbil.
Previous studies have shown depletion of monoamines in ischemic brain of the gerbil (9,11). When we subsequently investigated the differences in brain monoamine levels between those animals with cerebral ischemia alone and animals with ischemia that developed seizures, we found that catecholamines were only depleted in the seizure group thus raising the possibility that this was a secondary effect of seizure activity (10). Serotonin (5-HT), however, was decreased in both groups of animals. Since pharmacological depletion or elevation of brain 5-HT respectively facilitates or decreases seizure threshold in other epilepsy models (8), we have tested the hypothesis that depletion of brain 5-HT is a factor predisposing to the development of seizures in gerbils subjected to ischemia.
KeywordsSeizure Activity Seizure Onset Seizure Threshold Seizure Susceptibility Bilateral Common Carotid Artery
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