Abstract
Influences of 2.5 and 5% (
w
v
) aqueous tea and coffee beverages administered
ad lib. to rats for two weeks on PGI
2 synthesis by the rat thoracic aorta
in vitro were investigated using a rat platelet antiaggregatory bioassay and HPLC methods. The 2.5% beverages did not affect PGI
2 synthesis; however, the 5% beverages significantly decreased PGI
2 synthesis. The observed decreases were significantly abolished in presence of exogenous arachidonic acid suggesting a beverage-induced inhibition of precursor release. The ability of the beverages to inhibit PGI
2 synthesis may partly contribute towards better understanding of the biochemical mechanisms underlying some of the beverages-induced actions
in vivo.