Effect of a ginkgolide mixture (BN 52063) in antagonising skin and platelet responses to platelet activating factor in man.

Antagonism of the effects of platelet activating factor (PAF) by the ginkgolide mixture BN 52063 was assessed in a double-blind, placebo-controlled, crossover study in 6 normal subjects. Weal and flare responses to 400 ng PAF, examined 2 h after ingestion of BN 52063 (80 mg, 120 mg) were inhibited in a dose-related manner. After 120 mg the flare area was reduced by a mean 62.4% (p less than 0.005) and the weal volume by a mean 60% (p less than 0.05). Both doses of BN 52063 significantly inhibited PAF-induced platelet aggregation in platelet-rich plasma (p less than 0.001). In vitro, BN 52063 inhibited PAF-induced but not ADP-induced platelet aggregation. Thus BN 52063 seems to be an antagonist of PAF in man.