抄録
The present study was carried out to determine the relationship between the fatty acid composition of platelets and platelet aggregation in ischemic heart disease and to clarify the meaning of its atherogenesis. The cases studied were 19 patients with coronary heart disease (CHD group) including 9 patients with myocardial infarction (MI group) and 10 patients of angina pectoris with positive Master's test (EA group), 9 patients with negative Master's test (HD group) and 10 healthy control. In 24 of the 38 subjects the influence from exercise was investigated using the Master's double two step test. The results are as follows.
1) The linoleic acid content (18:2) of platelets and plasma was decreased in the CHD group and, in particular, in the MI group when compared with the N group.
2) In the MI group, the arachidonic acid content (20:4) of platelets was increased when compared with the N group, and the ratio of the linoleic acid content to the arachidonic acid content (20:4/18:2) of platelets was significantly higher than that in the N group. In the HD group and EA group, the arachidonic acid content of platelets was not increased when compared with the N group, while the ratio of the linoleic acid content to the arachidonic acid content of platelets tended to be higher than that in the N group.
3) Linoleic acid or arachidonic acid contents showed a significant correlation between in platelets and plasma.
4) ADP- and ADR-induced platelet aggreagtion was significantly accelerated in the CHD group and, in particular, in the EA group when compared with the N group, while collagen-induced platelet aggregation showed no difference between the N group and the CHD group.
5) A negative correlation between the linoleic acid content of platelets and ADP-induced platelet aggregation was observed.
6) Fatty acid composition in plasma showed no change by exercise, but the stearic acid content of platelets was decreased in the N group and the CHD group.
7) ADP and ADR-induced platelet aggregation was accelerated at mean values after exercise in all groups, there was no difference between any group. Collagen-induced platelet aggregation was markedly accelerated after exercise in the MI group when compared with the N group and the HD group.
From the above results, it was suggested that the linoleic acid content of platelets was closely related to platelet aggregation, and a decrease in linoleic acid, an increase in arachidonic acid and a high ratio of the linoleic acid content to the arachidonic acid content of platelets played a part of inducing coronary atherosclerosis or thrombosis.
