|
|
||||||||
Journal of Lipid Research, Vol 25, 1151-1158, Copyright © 1984 by Lipid Research, Inc.
AL Jones, GT Hradek, C Hornick, G Renaud, EE Windler and RJ Havel
In the rat, chylomicron remnants and very low density lipoprotein (VLDL)
remnants are taken up into the liver by high affinity processes and appear
to undergo degradation by lysosomes. The relationship of this catabolic
process to the known pathways of uptake and degradation of low density
lipoproteins (LDL) and the involvement of nonparenchymal cells are
addressed in these studies. We have utilized both light and electron
microscopic radioautography to determine whether the pathway of
intracellular transport and catabolism resembles that established for LDL
in hepatocytes. Radioiodinated plasma VLDL remnants and lymph chylomicron
remnants were injected into femoral veins of rats and the livers were fixed
by perfusion 3 to 30 minutes later. Quantitative light microscopic
radioautography showed little or no accumulation of grains over Kupffer
cells. Electromicroscopic radioautography confirmed these observations and,
in addition, demonstrated that very few grains were associated with
endothelial cells. The processing of the remnant particles closely
resembled that of LDL. Following an initial association of grains with the
parenchymal cell plasma membrane, frequently in regions in close proximity
to clathrin-coated endocytic pits, the grains were found in endocytic
vesicles just beneath the plasma membrane. By 15 minutes the grains were
found over multivesicular bodies located in the Golgi-lysosome region of
the cell. Thirty minutes after injection, radioautographic grains began to
be associated with secondary lysosomes. These data indicate no significant
role for nonparenchymal cells in the internalization and subsequent
degradation of triglyceride-rich lipoproteins, and provide evidence that
the processing of remnants as well as LDL follows the classical pathway of
receptor-mediated endocytosis.
ARTICLES
Uptake and processing of remnants of chylomicrons and very low density lipoproteins by rat liver
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
M D. Robertson, A. O Mason, and K. N Frayn Timing of vagal stimulation affects postprandial lipid metabolism in humans Am. J. Clinical Nutrition, July 1, 2002; 76(1): 71 - 77. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Heeren, T. Grewal, S. Jackle, and U. Beisiegel Recycling of Apolipoprotein E and Lipoprotein Lipase through Endosomal Compartments in Vivo J. Biol. Chem., November 2, 2001; 276(45): 42333 - 42338. [Abstract] [Full Text] [PDF] |
||||
![]() |
J Heeren, W Weber, and U Beisiegel Intracellular processing of endocytosed triglyceride-rich lipoproteins comprises both recycling and degradation J. Cell Sci., January 2, 1999; 112(3): 349 - 359. [Abstract] [PDF] |
||||
![]() |
Z.-S. Ji, H. L. Dichek, R. D. Miranda, and R. W. Mahley Heparan Sulfate Proteoglycans Participate in Hepatic Lipaseand Apolipoprotein E-mediated Binding and Uptake of Plasma Lipoproteins, Including High Density Lipoproteins J. Biol. Chem., December 12, 1997; 272(50): 31285 - 31292. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Journal of Biological Chemistry |
| Molecular and Cellular Proteomics | ASBMB Today |