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Decrease of extracellular catecholamine content in the vicinity of cortical penicillin-induced epileptogenic focus: voltammetric study in the rat.

J Pavlásek·P Mares·M Haburcák·C Masánová
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Abstract

Differential pulse voltammetry with carbon-fibre microelectrodes was used in chloralhydrate-anaesthetized rats to test the influence of the penicillin-G-Na (PNC)-induced (topical application, approximately 2000 IU) epileptic activity on the catecholamine content (catechol-oxidative current, CA.OC) in the parietal cortex. In the experimental group (n = 4) after PNC a nonlinear CA.OC lowering was observed; this decrease during the first 10 min was faster than in the control group (n = 4). Significantly different values were observed from the 4th min after application. The best fit for this experimental curve gave the logarithmic function (f(t) = a+b.ln(t), a = 105.8, b = -10.6) with regression coefficient r = 0.98. From the 12th min after PNC application until the end of the experiments (54th min) CA.OC values ranged from 78% to 84% of the control group.

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AnesthesiaAnimalsCatecholaminesCerebral CortexElectrodes, ImplantedElectroencephalographyElectrophysiologyEpilepsyExtracellular SpacePenicillinsRatsRats, WistarJournal ArticleResearch Support, Non-U.S. Gov't

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J Pavlásek, P Mares, M Haburcák, C Masánová. 1994. Decrease of extracellular catecholamine content in the vicinity of cortical penicillin-induced epileptogenic focus: voltammetric study in the rat.. https://doi.org/10.1007/bf00229113

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