Dietary fats and cholesterol supplementation effects on aortic and lipid response in rats

Abstract

The experiment was designed to elucidate the effects of feeding four dietary oils (corn, hazelnut, olive, and fish), and cholesterol supplementation on plasma, liver lipids, and aortic smooth muscle response to drugs. Male Sprague Dawley rats were fed semipurified diets containing one of the above oils (15% wt/wt), either with or without cholesterol supplementation (1% wt/wt), for 20 days. Hazelnut oil-fed rats showed the highest plasma total cholesterol level, while animals fed fish oil exhibited the lowest plasma total and high density lipoprotein cholesterol concentrations. Hepatic cholesterol content was not affected by dietary oils. Liver lipids increased when dietary cholesterol was added to any of the oils used. Acetylcholine pD 2 was elevated in fish oil- and hazelnut oil-fed rats, but rats fed all dietary oils showed maximal relaxation. Cholesterol supplementation reduced aortic maximal relaxation caused by acetylcholine. These results indicate that the type of dietary oil and cholesterol intake differentially raise plasma and liver lipid levels and modulate aortic smooth muscle response in the rat.