Effect of acetaldehyde on rat platelet aggregation in vivo and in vitro.

The effect of acetaldehyde on primary hemostasis and platelet aggregation was studied in vivo and in vitro in the rat. Acetaldehyde was found in circulation following ethanol intoxication or was present after direct i.v. injection. In vitro, acetaldehyde was added to whole blood or platelet plasma suspension. Bleeding time and blood loss were increased upon ethanol intoxication and immediately after i.v. infusion of acetaldehyde. The intrinsic coagulation system, assayed by APT-time, was unaffected. In vivo, ADP and collagen-induced platelet aggregation was inhibited upon the presence of acetaldehyde. In vitro, inhibition of platelet aggregation was observed when acetaldehyde was added to blood, while the addition of the compound to plasma did not affect platelet function.