Postprandial hyperlipemia in pigs

Abstract

The ability to induce postprandial hyperlipemia is essential for using certain animal species as models for short-term consequences of fat intake in humans. We present the results from two studies on postprandial hyperlipemia and triglyceride metabolism in young slaughter pigs using the proprietary lipid-containing product, Intralipid®. In the first study we demonstrated that postprandial hyperlipemia in slaughter pigs was insignificant (p=0.16) when fed Intralipid® in doses of 2 g fat/kg administered in two fractions: the first 1/3 11/2 hours after feeding, and the second 2/3 11/2 hours later. In the second study, induction of postprandial hyperlipemia was performed by administering Intralipid® in single doses of 2 g fat/kg 51/2 hours after feeding, which resulted in the development of significant postprandial hyperlipemia (p<0.001). To assess the half-life (T1/2) of triglycerides in the circulation, Intralipid® was administered intravenously in doses of 0.1 g fat/kg, which gave T1/2 (mean ± std.)=13.3±3.7 minutes. Furthermore, inhibiting the lipoprotein lipase by administering Triton WR-1339 intravenously in doses of 150 mg/kg exerted a significant inhibitory effect on the triglyceride catabolism in the circulation as determined by increments in peak value (p<0.05), increased area under the curve (iAUC) (p<0.01), and T1/2 (p<0.05). In conclusion, the slaughter pigs developed significant postprandial hyperlipemia when fed Intralipid® in doses of 2 g fat/kg 51/2 hours after feeding, while it was difficult to induce significant postprandial hyperlipemia when the same amount of fat was administered in two fractions in close proximity to feeding. We hypothesize that the high activity of the endothelial lipases, determined by the T1/2, constitutes the physiological threshold counteracting the development of postprandial hyperlipemia in young slaughter pigs.