Effects of ethanol on platelet thromboxane formation after ethanol withdrawal in chronic alcoholics: an in vitro...

The effect of ethanol on the formation of platelet thromboxane B2 (TXB2), a stable metabolite of thromboxane A2 (TXA2) was studied in vitro in six chronic alcoholics, admitted for detoxification, and in six healthy volunteers. Immediately after cessation of heavy drinking platelet count and ADP-induced TXB2 formation were lower in alcoholics than in nonalcoholic volunteers (P less than 0.05). Ten days after withdrawal of ethanol platelet count increased, and skin bleeding time shortened (P less than 0.05). Ethanol had no effect on arachidonate-induced platelet TXB2 formation, whereas ethanol added to platelet suspension prior to stimulation by ADP resulted in a concentration-related inhibitory tendency in both alcoholics and nonalcoholic control subjects. This effect of ethanol may be of significance for primary hemostasis in alcoholics.