Abstracts

Experimental and clinical studies have shown that prolonged seizures result in increased cytokine production in the central nervous system. However, the effect of seizure type on cytokine production is not well established. The purpose of this study is to examine the concentrations of two key cytokines in patients with temporal and extratemporal epilepsy undergoing a video-EEG study., Here we determined the levels of interleukin-6 (IL-6) and interleukin-1 receptor antagonist (IL-1RA) in serum from 20 patients before and after seizure during continuous video-EEG monitoring in Tampere University Hospital. In addition to baseline the blood samples were taken 3, 6, 12 and 24 hours after the seizure. The definition of the seizure focus and classification of epilepsy was based on concordant findings in this investigation, and on MRI examination. Patients were divided into two groups: temporal lobe epilepsy (n=11), and extratemporal epilepsy (n=9)., In the patients with seizures originating from temporal (p[lt] 0.01) and extratemporal lobes (p[lt] 0.05) there was a statistically significant increase in the levels of IL-6 production after the seizure. Moreover, the concentrations of IL-6 were significantly higher in temporal lobe group compared with extratemporal group (p=0,016). In the patients with temporal seizures there was a significant decrease in the levels of IL-1RA production (p[lt]0.05) but not in the patients with extratemporal seizures., The present study demonstrates that single seizures in chronic epilepsy are followed by activation of cytokine network. The production of IL-1RA and IL-6 are influenced by the origin of the seizures from either temporal or extratemporal lobes. Experimental studies have demonstrated that IL-1RA may act as an anticonvulsant and neuroprotectant, whereas IL-6 seems to be proconvulsant and neurotoxic. Differential activation of these key cytokines may modify central nervous system reactions to seizures.,