Influence of antioxidants on the blood-brain barrier permeability during epileptic seizures.
Pentylenetetrazol-induced seizures in rats lead to the breakdown of the blood-brain barrier. We compared the disruption of the blood-brain barrier during epileptic seizure in untreated rats and in rats treated with vitamin E or selenium. The rats were supplemented with nontoxic doses of sodium selenite (4 pp) in drinking water for 3 months, or vitamin E (70 mg/kg) was given intraperitoneally for 30 min before the pentylenetetrazole injection. Evans-blue was used as a blood-brain barrier tracer and was given intravenously at a dose of 4 ml/kg of a 2% solution. The rats were divided into four experimental groups. Group I: control (n = 24); Group II: pentylenetetrazole-induced seizure (n = 12); Group III: vitamin E injected + seizure (n = 12); Group IV: Selenium supplemented + seizure (n = 12). The rats subjected to epileptic seizures showed Evans-blue albumin extravasations especially in the thalamic nuclei, brainstem, occipital, and frontal cortex. Mean values for Evans-blue dye were found to be 0.28 +/- 0.04 mg % brain tissue in control rats and 1.6 +/- 0.2 mg % brain tissue after epileptic seizures (P < 0.01). The magnitude of distribution of the blood-brain barrier during epileptic seizures was significantly less in rats treated with vitamin E or selenium. The mean value for Evans-blue dye was found to be 1.2 +/- 0.1 mg % brain tissue in selenium supplemented rats and 1.2 +/- 0.1 mg % brain tissue in vitamin E injected rats after epileptic seizures. This difference between treated and untreated animals was found to be significant (P < 0.05). The findings of the present study suggest that free radicals contribute to disruption of the blood-brain barrier during pentylenetetrazol-induced seizures.
Oztaş
B
B
Department of Physiology, Istanbul Faculty of Medicine, University of Istanbul, Capa Istanbul, Turkey. bariaoztas@hotmail.com
Kiliç
S
S
Dural
E
E
Ispir
T
T
D000418:Albumins / Q000493:pharmacokinetics; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001812:Blood-Brain Barrier / Q000187:drug effects* / Q000502:physiology; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D004396:Coloring Agents / Q000493:pharmacokinetics; D003292:Convulsants / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D004827:Epilepsy / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D005070:Evans Blue / Q000493:pharmacokinetics; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D005609:Free Radicals / Q000037:antagonists & inhibitors / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D010433:Pentylenetetrazole / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012643:Selenium / Q000494:pharmacology*; D014810:Vitamin E / Q000494:pharmacology*
D000418:Albumins; D000975:Antioxidants; D004396:Coloring Agents; D003292:Convulsants; D005609:Free Radicals; D018696:Neuroprotective Agents; D014810:Vitamin E; D005070:Evans Blue; D012643:Selenium; D010433:Pentylenetetrazole