DAILY VARIATION OF SERUM-LIPIDS IN RELATION TO THE CIRCADIAN-RHYTHM OF PLATELET-AGGREGATION IN HEALTHY MALE PERSONS

The circadian rhythm of platelet aggregation was compared with that of serum lipids in seven healthy male persons, Daily variations of remnant lipoprotein-cholesterol and of remnant lipoprotein-triglycerides were related to those of arachidonic acid-, ADP (adenosine diphosphate)-, and collagen-induced aggregation in platelet-rich plasma and to ADP-induced aggregation in whole blood, respectively. Statistical analyses indicate that the time course of remnant-cholesterol was correlated to that of ADP-induced aggregation in platelet-rich plasma and the time courses of blood cholesterol and triglyceride were correlated to arachidonic acid- and serotonin-induced platelet aggregation in platelet-rich plasma, respectively. In whole blood, the time course of remnant lipoprotein-triglyceride was correlated only to ADP-induced platelet aggregation. In contrast, the daily variation of HDL (high density lipoprotein)-cholesterol did not influence either that of platelet aggregation in platelet-rich plasma or that in whole blood, Our findings are of clinical interest regarding the development of atherosclerosis and thrombotic events in persons with an elevated level of serum lipids.