Journal of Lipid Research, Vol 29, 713-720, Copyright © 1988 by Lipid Research, Inc.

ARTICLES

Regulation of the metabolism of lipid emulsion model lipoproteins by a saturated acyl chain at the 2-position of triacylglycerol

BC Mortimer, WJ Simmonds, CA Joll, RV Stick and TG Redgrave
Department of Physiology, University of Western Australia, Nedlands.

Lipid emulsion particles were prepared by sonicating four different lipid mixtures (triacylglycerol (TAG), 70%; phospholipid, 25%; cholesteryl oleate (CO), 3%; and free cholesterol, 2%), then purified by density gradient ultracentrifugation. For three test mixtures, the TAG contained 50, 75, or 100% 1,3-dioleyl-2-stearylglycerol (OSO) with the remainder being triolein (OOO); 100% triolein in the lipid mixture was used as the control. After intravenous injection of the lipid particles into unanesthetized rats, removal of radioactive TAG fatty acid and CO from plasma was measured for 30 min, then liver and spleen uptakes were measured. When emulsions contained 75% or 100% OSO as TAG, the plasma removal rates of CO were, respectively, 60% or 30% of the rate when the TAG was 100% triolein; smaller recoveries of CO were found in the liver. The clearances of TAG fatty acid did not differ significantly and the recoveries of TAG fatty acid in the organs were not affected by the type of emulsion injected. Remnant particles were derived from donor rats in which uptake was blocked by exclusion of liver and other viscera from the circulation before injection of 100% OOO and 100% OSO emulsions. When injected into recipient intact rats, the removal of remnants from plasma was slower for remnants derived 15 min after injection of 100% OSO emulsions than from 100% OOO emulsions, showing that the slower removal of emulsion CO was due to slower remnant uptake from the plasma with OSO emulsions.(ABSTRACT TRUNCATED AT 250 WORDS)
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K. M. Yli-Jokipii, U. S. Schwab, R. L. Tahvonen, J.-P. Kurvinen, H. M. Mykkanen, and H. P. T. Kallio Triacylglycerol Molecular Weight and to a Lesser Extent, Fatty Acid Positional Distribution, Affect Chylomicron Triacylglycerol Composition in Women J. Nutr., May 1, 2002; 132(5): 924 - 929. [Abstract] [Full Text] [PDF]

				K. Yli-Jokipii, H. Kallio, U. Schwab, H. Mykkanen, J.-P. Kurvinen, M. J. Savolainen, and R. Tahvonen Effects of palm oil and transesterified palm oil on chylomicron and VLDL triacylglycerol structures and postprandial lipid response J. Lipid Res., October 1, 2001; 42(10): 1618 - 1625. [Abstract] [Full Text] [PDF]

				L. K. M. Summers, B. A. Fielding, S. L. Herd, V. Ilic, M. L. Clark, P. T. Quinlan, and K. N. Frayn Use of structured triacylglycerols containing predominantly stearic and oleic acids to probe early events in metabolic processing of dietary fat J. Lipid Res., October 1, 1999; 40(10): 1890 - 1898. [Abstract] [Full Text]

				C. T Phan, B.-C. Mortimer, I. J Martins, and T. G Redgrave Plasma clearance of chylomicrons from butterfat is not dependent on saturation: studies with butterfat fractions and other fats containing triacylglycerols with low or high melting points Am. J. Clinical Nutrition, June 1, 1999; 69(6): 1151 - 1161. [Abstract] [Full Text] [PDF]

				B.-J. Zeng, B.-C. Mortimer, I. J. Martins, U. Seydel, and T. G. Redgrave Chylomicron remnant uptake is regulated by the expression and function of heparan sulfate proteoglycan in hepatocytes J. Lipid Res., April 1, 1998; 39(4): 845 - 860. [Abstract] [Full Text]

				S. Aoe, J.-i. Yamamura, H. Matsuyama, M. Hase, M. Shiota, and S. Miura The Positional Distribution of Dioleoyl-Palmitoyl Glycerol Influences Lymph Chylomicron Transport, Composition and Size in Rats J. Nutr., July 1, 1997; 127(7): 1269 - 1273. [Abstract] [Full Text]