Antihypertensive properties of linoleic acid and fish oil omega-3 fatty acids independent of the prostaglandin system.
Polyunsaturated fatty acids of the omega-6 and the omega-3 series have been shown to lower arterial pressure in humans and in various models of experimental hypertension by uncharacterized mechanisms. The objectives of our study were to compare the antihypertensive properties of linoleic acid (omega-6 series) and of fish oil fatty acids (omega-3 series) in a model of hypertension induced by the continuous subcutaneous infusion of angiotensin II in the rat and to determine whether or not their antihypertensive effects were mediated by the biosynthesis of vasodilator prostaglandins of classes 2 or 3. Linoleic acid and fish oil fatty acids (administered by subcutaneous injections) were equally potent in reducing, by half, the rise in systolic arterial pressure induced by the chronic infusion of angiotensin II. These antihypertensive effects were observed in the absence of any significant influence of either linoleic acid or fish oil fatty acids on the systemic and the renal synthesis of PGI2 or on the renal formation of PGE2 in vivo. Indomethacin caused a profound inhibition of the biosynthesis of PGI2 but not of PGE2 and could only partially neutralize the antihypertensive effects of linoleic acid and of fish oil fatty acids. These results suggest that, in this model of angiotensin II-induced hypertension, linoleic acid and fish oil fatty acids exert equipotent antihypertensive effects which are mainly independent of the prostaglandin system.
Hui
R
R
Laboratory on Prostaglandins, Clinical Research Institute of Montreal, Quebec, Canada.
St-Louis
J
J
Falardeau
P
P
D000804:Angiotensin II / Q000009:adverse effects; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects*; D015118:Eicosapentaenoic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D005395:Fish Oils / Q000494:pharmacology; D006973:Hypertension / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D007213:Indomethacin / Q000494:pharmacology; D008041:Linoleic Acids / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D010656:Phenylephrine / Q000494:pharmacology; D011453:Prostaglandins / Q000652:urine*; D051381:Rats; D011919:Rats, Inbred Strains; D012083:Renin / Q000097:blood
D005395:Fish Oils; D008041:Linoleic Acids; D011453:Prostaglandins; D000804:Angiotensin II; D010656:Phenylephrine; C035276:eicosapentaenoic acid ethyl ester; D015118:Eicosapentaenoic Acid; D012083:Renin; D007213:Indomethacin