Effect of varying concentrations of linoleic acid on alpha-adrenoceptor responses in spontaneously hypertensive rats.
The effect of increased intake of linoleic acid on the alpha-adrenergic system was assessed by safflower oil supplementation to spontaneously hypertensive rats. Linoleic acid-enriched intake at 5%, 15% and 30% by weight of total food intake for 12 wk was associated with a reduction in resting arterial blood pressure, while heart rate and heart to body weight ratios were similar to control group values. A dose-response analysis to norepinephrine bitartrate administered intravenously indicated a significant reduction in the vascular reactivity to this alpha-adrenergic agonist in all groups given linoleic acid. Direct assessment of alpha-adrenoceptor number (Bmax) and affinity (KD) in cardiac sarcolemma with [3H]-prazosin indicated that receptor binding properties were not affected by linoleic acid intake. Our results suggest that short-term linoleic acid supplementation in the established hypertensive state may lower blood pressure through effects upon alpha-adrenergic reactivity in vascular tissue, without associated effects in cardiac tissue.
Crandall
D L
DL
Medical Research Division, American Cyanamid Company, Pearl River, New York 10965.
Goldstein
B M
BM
Lozito
R J
RJ
Lizzo
F H
FH
Cervoni
P
P
D000818:Animals; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D006439:Hemodynamics / Q000187:drug effects; D006973:Hypertension / Q000378:metabolism*; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*
D005231:Fatty Acids, Unsaturated; D008041:Linoleic Acids; D011942:Receptors, Adrenergic, alpha; D019787:Linoleic Acid