Xanthine Oxidase Potentiation of Reactive Oxygen Intermediates in Isolated Canine Peripheral Neutrophils.

摘要

Oxygen-derived free radicals are believed to contribute to reperfusion injury based, in part, upon results conferred by the pharmacologic administration of allopurinol. Allopurinol inhibits xanthine oxidase (XO) activity ischemic tissues. The possible role of XO as a pathologic mediator prompted examination of its effects on isolated peripheral canine neutrophils. In contrast to neutrophils alone, or following stimulation with phorbol myristate acetate (PMA), it was determined that XO affected both the membrane potential and the metabolism significantly. Membrane potential assay showed that at 5-10 min, PMA depolarized 89-96% of the canine neutrophils between 32-48%. Incubation with 0.5 U/ml XO involved fewer cells (54-86%), but at substantially increased cellular depolarization levels (76-90%).