Improvement of postischemic dopaminergic dysfunction by edaravone, a free radical scavenger.
Effects of a free radical scavenger, edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), on ischemia/reperfusion-induced dysfunctions of rat striatal dopaminergic neurons were examined using in vivo brain microdialysis. During transient forebrain ischemia, dopamine levels in dialysates were elevated 140-fold above controls but rapidly recovered after reperfusion. The increase in dopamine levels induced by high K+ stimulation after reperfusion was far smaller than that of the controls. Pretreatment with edaravone but not post-treatment dose-dependently improved the response to high K+ but not the massive dopamine increase during ischemia. These results suggest that free radicals produced during ischemia play more important roles in ischemia/reperfusion-induced dysfunctions of dopaminergic neurons.
Akiyama
Yoshinori
Y
Department of Neurosurgery, Tenri Hospital, Nara, and Department of Cellular Pharmacology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Miwa
Soichi
S
D000818:Animals; D000983:Antipyrine / Q000031:analogs & derivatives* / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015314:Dialysis Solutions / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D000077553:Edaravone; D016166:Free Radical Scavengers / Q000494:pharmacology*; D002546:Ischemic Attack, Transient / Q000503:physiopathology; D008297:Male; D017551:Microdialysis; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar
D015314:Dialysis Solutions; D016166:Free Radical Scavengers; D011188:Potassium; D000077553:Edaravone; D000983:Antipyrine; D004298:Dopamine