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Omega-3 fatty acids reduce blood pressure, plasma thromboxane B-2 and stress response in patients with essential hypertension

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Abstract

The blood pressure-lowering effect of dietary omega-3 fatty acids in hypertensive patients is well established. Of the various mechanisms involved a decrease of the vasoconstrictory and proaggregatory thromboxane A(2) plays a dominating role. Considering literature data plasma thromboxane B-2, the stable metabolite of thromboxane A(2), and blood pressure response were studied within a standardized psychophysiological stress test in three intervention trials. In the first study in 44 patients with mild essential hypertension the effects of oleic (n-9), linoleic (n-6) and alpha-linolenic (n-3) acid were compared. The patients received an isocaloric diet supplemented with olive, sunflower- and linseed oil, respectively. After linseed oil a slight but significant depression of blood pressure and stress response was observed. In two subsequent studies, dietary supplementation with canned mackerel or encapsulated fish oil concentrate resulted in an even more pronounced reduction of blood pressure and stress response which was associated with a significant decrease of the vasoconstrictory and proaggregatory plasma thromboxane B-2. The results indicate a hitherto ignored effect of polyunsaturated omega-3 fatty acids which could be of some importance for the prevention of coronary heart disease.

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