ABSTRACT
When the phospholipids from pyuria were diluted with BSA/saline and added to washed rabbit platelets, platelet aggregation decreased. By contrast, Nakayama et al. (14) reported that when similarly prepared samples from rat uterus were diluted with BSA/saline and added to washed rabbit platelets, platelet aggregation increased. This discrepancy was explained by the presence of endogenous inhibitors, such as lysophosphatidylcholine and sphingo-myelin, in rat uterine samples. In our samples, the content of inhibitors was apparently insufficient to interfere with the platelet aggregation assay, even if endogenous inhibitors would have been present. The amount of PAF in urine was determined based on the aggregating activity of the phospholipid fraction obtained by column chromatography.
