Abstract
A possibility of association between the platelet aggregation and active oxygens was investigated. The ADP-, collagen-, thrombin- or epinephrin-induced platelet aggregations in PRP were inhibited by addition of Tiron, 1, 4-Diazabicyclooctane (DABCO) and 2, 5-Dimethylfuran (DMF), the scavengers on superoxide radical (O2-) and singlet oxygen (1O2). The arachidonic acid-induced platelet aggregation was not inhibited by the scavengers. The scavengers on hydroxyradial (·OH) and hydrogen peroxide (H2O2), mannose and catalase, respectively, did not affect on the all platelet aggregations examined in this work. The results of platelet aggregometry, release reaction of 3H-serotonin and electron microscopy demonstrated that human platelets were aggregated by incubation with xanthine-xanthine oxidase system (active oxygens producing system). Furthermore, the aggregation caused by this system was inhibited by addition of superoxide dismutase, DABCO and DMF. These results suggested that these aggregations were induced by O2- and 1O2. It was postulated that active oxygens would participate in the process of platelet aggregation, as this was induced by the active oxygens generating system and ADP-, collagen-, thrombin- or epinephrine-induced aggregations were inhibited by addition of the scavengers of O2- and 1O2.
