Effect of quercetin on chemiluminescence of human platelets induced by arachidonic acid
Gu, Z.L.; Xie, M.L.; Qian, Z.N.
Zhongguo Yao Li Xue Bao 14(3): 263-265
1993
ISSN/ISBN: 0253-9756 PMID: 8237407 Document Number: 412716
Arachidonic acid (AA)-induced platelet chemiluminescence (CL) was measured with a lumiphotometer. Quercetin remarkably inhibited the CL, the IC-50 of quercetin was 3 mu-mol cntdot L-1. When quercetin plus aspirin, which inhibits only cyclooxygenase, was added, the inhibitory rate of platelet-CL obviously increased (P lt 0.01). On the other hand, the quercetin had a scavenging effect on superoxide anion radical using alkaline sodium dithionite solution generation. The IC-50 was 20.9 mu-mol cntdot L-1. In addition, superoxide dismutase of 0.1 mg cntdot ml-1 inhibited the platelet-CL by 97.8%, while mannitol, a hydroxyl radical scavenger, only by 43.3% at a concentration of 80 mg cntdot ml-1. These results suggest that the mechanism of the inhibiting AA-induced platelet-CL by quercetin was associated with scavenging the superoxide anion radical directly and with inhibiting the cyclooxygenase.