[Platelet aggregation in whole blood and prostacyclin in hyperlipemia types II and IV].

Platelets play an essential role in the pathogenesis of atherosclerosis. Prostacyclin is a strong physiological inhibitor of platelets aggregation; prostacyclin indeed is involved in the regulation of platelet interactions with vessel walls and is considered to play a major role in the homeostatic balance. The impedance aggregometry allows the evaluation of platelet aggregation in whole blood. We valued platelet aggregation in whole blood induced by ADP (10 microM) in 40 healthy subjects and in 40 type II and type IV hyperlipemic subjects. Meanwhile by radioimmunoassay we dosed 6-keto PGF1 alpha, a stable product of prostacyclin, in 7 healthy subjects and in 33 hyperlipemic subjects. The statistical investigation put in evidence that at higher plasmatic levels of cholesterol, triglycerides and LDL correspond a greater platelet sensitivity to the aggregating agent, while the opposite happens to higher levels of HDL. The dosage of 6-keto PGF1 alpha put in evidence an increase of this substance in hyperlipemic as to healthy subjects, probably as an answer to augmented platelet aggregation.