Abstract
The relationship between platelet life-span and plasma concentration of β-thromboglobulin (β-TG) or platelet factor 4 (PF-4) was studied in 28 normal subjects and 69 patients with various diseases (9 patients with essential hypertension, 12 patients with diabetes mellitus, 6 patients with malignant tumor, 24 patients with cerebral infarction, 13 patients with ischemic heart disease and 5 patients with peripheral vessel thrombosis). The platelet life-span was measured by means of a non-radioisotopic method using aspirin. The following results were obtained :
1. The mean platelet life-span in each disease group except for essential hypertension was reduced significantly compared with that of the healthy control group.
2. The plasma concentrations of β-TG and PF-4 in the cerebral infarction and ischemic heart disease groups were elevated significantly compared with those of the healthy control group.
3. Among all the patients and normal control individuals subjected to the present study, a significant inverse correlation was confirmed between the platelet life-span and the plasma concentration of β-TG or PF-4. The correlation was also significant in each disease group except for the malignant tumor and peripheral vessel thrombosis groups.
4. The platelet life-span was correlated inversely and significantly with the plasma concentration of fibrinogen, but was not correlated with either the serum concentration of total cholesterol, HDL-cholesterol or triglyceride.
5. In patients with cerebral infarction and ischemic heart disease, the shortened platelet life-span and increased plasma concentration of β-TG or PF-4 tended to be normalized as the time interval between the attack and their respective measurements increased.
From these results, it was concluded that the intravascular platelet consumption in patients with the various diseases described above was increased significantly, and that plasma concentrations of β-TG and PF-4 are reliable indicators of the platelet consumption.
