Influence of vitamin e administration on platelet functions in hormonal contraceptive users
Renaud, S.; Ciavatti, M.; Perrot, L.; Berthezene, F.; Dargent, D.; Condamin, P.
Contraception 36(3): 347-358
1987
ISSN/ISBN: 0010-7824 PMID: 3677678 DOI: 10.1016/0010-7824(87)90105-3Document Number: 356002
Platelet functions (aggregation, clotting activity), platelet lipid biosynthesis, sterol composition and phospholipid fatty acids were studied in relation to plasma lipids and fatty acids as well as dietary habits at day 5 and 21 of the menstrual cycle in 30 women who used oral contraceptives (OCs) for several years. The women were studied again on day 21 of the 2nd cycle after they had taken 200 mg vitamin E/day for 2 months in addition to the OCs. At day 21 (after 3 weeks of OC use) there was a significant increase in the clotting activity of platelets and the response to ADP-induced aggregation concomitant with a decrease in plasma vitamin E. After vitamin E administration, platelet activity at day 21 was markedly decreased, being similar to the activity at day 5, along with a significant increase in the level of vitamin E in plasma and platelets. The high response of platelets to aggregation in women taking OCs does not seem to be associated with the intake of saturated fat but rather with that of 18:2. The aggregation to thrombin was mostly related to lanosterol biosynthesis and the aggregation to ADP to platelet cholesterol, but not to plasma lipids or apoproteins. The present pilot study suggests that the platelet hyperactivity of longterm OC users might be dependent on a low level of platelet alpha-tocopherol which can be rapidly overcome by administering a vitamin E supplement.