Regulation of Dietary Fatty Acid Entrapment in Subcutaneous Adipose Tissue and Skeletal Muscle

Using stable isotopic labeling of dietary fatty acids in conjunction with arteriovenous difference measure-ments, we have assessed the regulation of lipoprotein lipase–derived fatty acid entrapment in subcutaneous adipose tissue and forearm muscle in healthy subjects in the postprandial state. Eight volunteers fasted over-night and were then given a mixed meal containing [1-13C]palmitic acid and [1-13C]oleic acid. At baseline and for 6 h after the meal, blood samples were obtained from an arterialized hand vein and veins draining sub-cutaneous abdominal adipose tissue and forearm mus-cle, and arteriovenous differences were calculated. Entrapment of labeled fatty acids released by circulat-ing triacylglycerol hydrolysis was close to 100 % at 60 min, decreasing to 10–30 % by 360 min. Entrapment o