Effect of acute ethanol intake on thromboxane and prostacyclin in human.

To investigate the effects of acute ethanol administration on the production of proaggregatory thromboxane A2 (TxA2) and antiaggregatory prostacyclin (PGI2), ethanol (1.5 g/kilogram body weight) was given to eight healthy nonsmoking men, and the stable metabolites thromboxane B2 (TxB2) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), respectively, measured by radioimmunoassay from serial blood samples before drinking and during the ensuing 18 hours. Each subject was studied as his own control on another occasion when only an equivalent volume of water was given. Serum TxB2 level decreased (p less than 0.01) from 206 +/- 31 ng/ml (mean +/- S.E.) to 167 +/- 24 and 161 +/- 23 ng/ml (two and four hours after beginning of the drinking, respectively) concomitantly with the attainment of maximal blood ethanol concentrations (about 120 mg/100 ml), whereas no changes occurred in plasma 6-keto-PGF1 alpha concentrations. Our results may provide an explanation for known effects of ethanol on platelet aggregation. They also raise speculation whether TxA2-inhibition and the antiatherogenic effect of alcohol intake are somehow related.