Abstracts

RATIONALE: Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) commonly used to treat depression in humans and animals. Trifluoromethylphenylpiperazine (TFMPP) is a serotonin 1A/1B and 2A/2C receptor agonist. SSRIs have been thought to increase seizures in patients suffering from epilepsy. Experimental studies in evoked-seizure models have suggested that SSRIs reduce seizures. This study tested the hypothesis that fluoxetine and TFMPP reduce seizure rate in rats with pilocarpine-induced epilepsy. METHODS: Adult male Sprague-Dawley rats were used 3-7 mo after pilocarpine treatment. All rats had spontaneous seizures. Phenobarbital was administered as a positive control at 10 mg/kg. Saline was given as the control at an equal volume (i.e. 0.5 ml). Fluoxetine was administered at 20 mg/kg. TFMPP was administered at 5 mg/kg. All drugs were administered intraperitoneally once per day. Each rat received each treatment for five consecutive days with a 1-wk interval between each treatment. Rats were continuously video monitored for the last 72 h of each treatment. Seizures were graded using the Racine Scale (Racine, 1972). Class I and II seizures were not scored. RESULTS: Seizure rates for the different treatments were compared using a paired t-test. The spontaneous seizure rate for phenobarbital- and fluoxetine-treated rats was reduced compared to saline-treated animals. However, TFMPP at 5 mg/kg did not reduce the spontaneous seizure rate compared to saline. CONCLUSIONS: The available data from this preliminary study suggest that a short-term dose of fluoxetine reduces the rate of spontaneous seizures, but TFMPP has no effect on the seizure rate in this rat model of temporal lobe epilepsy. Suppoted by NS16683