Arachidonic acid does not share the antihypertensive properties of linoleic acid and fish oil omega-3 fatty acids in a model of angiotensin II-induced hypertension in the rat.

Linoleic acid and fish oil omega-3 fatty acids, but not arachidonic acid, exerted antihypertensive effects in a model of angiotensin II-induced hypertension in rats. Indomethacin did not influence the systolic arterial pressure of arachidonic acid-treated hypertensive rats whereas compound L-641,953, a prostaglandin H2/thromboxane A2 receptor antagonist, caused a notable but statistically nonsignificant decrease in blood pressure in these animals. Although these results do not exclude entirely the possibility that the lack of antihypertensive effect of arachidonic acid may be due, in part, to the concomitant formation of vasoconstrictor prostanoids, they do not support it. These observations, as well as those of a previous study, indicate that linoleic acid and fish oil omega-3 fatty acids exert antihypertensive effects of their own, independently of the prostanoid system, and that these properties are not shared by arachidonic acid.