Intracranial microdialysis of salicylic acid to detect hydroxyl radical generation by monoamine oxidase inhibitor in the rat.
The effect of pargyline, a monoamine oxidase inhibitor, on the generation of hydroxyl free radicals (OH) was investigated using striatal microdialysis. Salicylic acid in Ringer's solution (0.5 nmol microliter-1 min-1) was infused through a microdialysis probe to detect the generation of hydroxyl radicals (OH) as reflected by the formation of dihydroxybenzoic acid (DHBA) in the striatum. When pargyline (100 nmol microliter-1 min-1) was infused in rat brain, the level of 3,4-dihydroxyphenylacetic acid (DOPAC) gradually decreased in a time-dependent manner. In addition, a marked elevation of DHBA was observed. The present results indicate that accumulation of dopamine (DA) in the extracellular fluid elicited by pargyline can be auto-oxidized, which in turn leads (possibly by an indirect mechanism) to the formation of cytotoxic OH free radicals.
Obata
T
T
Department of Pharmacology, Oita Medical University, Japan.
Yamanaka
Y
Y
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D001927:Brain Diseases / Q000378:metabolism; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D005609:Free Radicals / Q000378:metabolism; D017665:Hydroxyl Radical / Q000378:metabolism*; D008297:Male; D017551:Microdialysis; D010293:Pargyline / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012459:Salicylates / Q000008:administration & dosage / Q000378:metabolism*; D020156:Salicylic Acid; D013997:Time Factors
D005609:Free Radicals; D012459:Salicylates; D015102:3,4-Dihydroxyphenylacetic Acid; D017665:Hydroxyl Radical; D010293:Pargyline; D020156:Salicylic Acid; D004298:Dopamine