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Updated: Aug 1, 2026

Turbidimetry on Human Washed Platelets: The Effect of the Pannexin1-inhibitor Brilliant Blue FCF on Collagen-induced Aggregation
Published on: April 6, 2017
Biphasic modulation of platelet phospholipase A2 activity and platelet aggregation by mepacrine (quinacrine)
Abstract:
The modulation of rat platelet phospholipase A2 (phosphatide 2-acylhydrolase, EC 3.1.1.4) and rat platelet aggregation by mepacrine was investigated. The 2-acyl specificity of phospholipase A2 activity was confirmed by using 1-[14C]palmitoyl-2-[3H]arachidonylphosphatidylcholine as substrate. Under optimal pH, phospholipase A2 activity was not affected by aspirin but was inhibited by indomethacin. Contrary to previous reports, a biphasic modulatory role of mepacrine on phospholipase A2 activity and platelet aggregation was demonstrated. The data suggest that platelet aggregation is mediated via phospholipase A2.
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