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Determination of hydroxyl free radical formation in human platelets using high-performance liquid chromatography with electrochemical detection.
No full textThe formation of the hydroxyl free radical (HFR) can be quantified indirectly, by measuring two products of the hydroxylation of salicylic acid, 2,3-dihydroxybenzoate (2,3-DHB) and 2,5-dihydroxybenzoate (2,5-DHB). In this study, we used reversed-phase high-performance liquid chromatography with electrochemical (coulometric) detection to measure 2,3- and 2,5-DHB levels in human platelets. The limits of detection of the method were 10 and 5 fmol on column for 2,3-DHB and 2,5-DHB, respectively. We tested the technique by measuring increases in dihydroxybenzoate levels after exposure of platelets to experimentally induced oxidative stress. Then, we measured platelet levels of 2,3- and 2,5-DHB in patients with Parkinson's disease, under therapy with L-DOPA, and in normal subjects. We also measured platelet concentrations of L-DOPA and its major metabolite, 3-O-methyldopa (3-OMD). Parkinsonian patients showed increased levels of both 2,3- and 2,5-DHB. Platelet levels of 2,3-DHB were positively correlated with platelet levels of L-DOPA and 3-OMD. The technique we describe proved simple and extremely sensitive and may represent a useful tool for the study of oxidative stress in humans. Copyright (C) 1999
Modifications of some clotting and lipidic fractions in liver malignant and benign diseases.
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