Arachidonic acid supplementation dose-dependently reverses the effects of a butter-enriched diet in rats.
Male Sprague Dawley rats were fed a butter-enriched diet (50% fat) for 2 weeks which was supplemented orally with 9, 18, 36, or 72 mg/day of ethyl arachidonate for a further 2 weeks. The control group of animals were fed a 5% fat diet for 4 weeks. Aortic prostacyclin (PGI2) production, platelet aggregation and thromboxane A2 (TXA2) production and plasma and aortic phospholipid (PL) fatty acids were measured. 50% butter-feeding resulted in a significant reduction in aortic PGI2 production and collagen-induced platelet aggregation and TXA2 production. These changes were accompanied by a reduction in plasma and aortic PL arachidonic acid levels and an increase in eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), 5,8,11-eicosatrienoic acid (ETA) and dihomo-gamma-linolenic acid (DGLA). These changes in prostanoid production, platelet aggregation and PL fatty acid composition were dose-dependently reversed by the daily oral administration of ethyl arachidonate (9, 18, 36, or 72 mg). The threshold dose being as little as 9 mg of ethyl arachidonate/rat/day for reversal of PL fatty acid composition, collagen-induced platelet aggregation and TXA2 production, and 18 mg of ethyl arachidonate/rat/day for reversal of aortic PGI2 production. Full reversal was seen generally with 36 or 72 mg of ethyl arachidonate/rat/day. The data highlight the responsiveness of tissue eicosanoid production to small quantities (ppm) of dietary eicosanoid precursors.
Steel
M S
MS
University of Melbourne, Department of Medicine, Royal Melbourne Hospital, Parkville, Victoria, Australia.
Naughton
J M
JM
Hopkins
G W
GW
Sinclair
A J
AJ
O'Dea
K
K
D000818:Animals; D001012:Aorta, Abdominal / Q000187:drug effects / Q000378:metabolism; D001095:Arachidonic Acids / Q000008:administration & dosage*; D002079:Butter; D003094:Collagen / Q000494:pharmacology; D004041:Dietary Fats / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D011464:Epoprostenol / Q000096:biosynthesis; D005227:Fatty Acids / Q000097:blood / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D010743:Phospholipids / Q000097:blood / Q000378:metabolism; D010974:Platelet Aggregation / Q000187:drug effects; D051381:Rats; D013928:Thromboxane A2 / Q000096:biosynthesis
D001095:Arachidonic Acids; D004041:Dietary Fats; D005227:Fatty Acids; D010743:Phospholipids; C035723:ethyl arachidonate; D013928:Thromboxane A2; D002079:Butter; D003094:Collagen; D011464:Epoprostenol