Circadian rhythms of the functions of thrombocytes and basophils in the blood of healthy volunteers and of patients with ischaemic heart disease.

The circadian rhythms of the functions of the cellular components of haemostasis, and their response to administration of ACTH, were studied in 30 healthy volunteers and in 17 patients with cardiosclerosis secondary to past myocardial infarction. A biphasic periodicity was found of the counts and functional activities of thrombocytes and basophilic leukocytes during 24-h periods. The phase of peak activities of both formed blood elements was established between 11.00 and 14.00 hours; in the night their functional capacities were lower than in the morning. Administration of ACTH elicited analogous shifts in the above mentioned indicators, but with a faster development of the first phase. In ischaemic heart disease the normal circadian rhythm of functions of the specified indicators was disturbed, and they exhibited signs of inertia, which phenomenon, in the author's opinion, reflects a lowered reliability of function of the haemostatic system.