Decrease of extracellular catecholamine content in the vicinity of cortical penicillin-induced epileptogenic focus: voltammetric study in the rat.
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.
Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovak Republic.
J
J
Pavlásek
P
P
Mares
M
M
Haburcák
C
C
Masánová
D000758:Anesthesia; D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism* / Q000503:physiopathology; D004567:Electrodes, Implanted; D004569:Electroencephalography; D004594:Electrophysiology; D004827:Epilepsy / Q000139:chemically induced / Q000378:metabolism* / Q000503:physiopathology; D005110:Extracellular Space / Q000378:metabolism*; D010406:Penicillins; D051381:Rats; D017208:Rats, Wistar
D002395:Catecholamines; D010406:Penicillins