Metabolic fate of rat and human lipoprotein apoproteins in the rat
The fate of 125I-labeled apolipoproteins was studied in vivo in rats that had received intravenous injections of 125I-labeled rat HDL and 125I-labeled human HDL, LDL, and VLDL.Plasma decay curves of rat and human HDL were exponential with similar half-lives in the circulation (11–12 hr). After injec...
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doaj-c2ccc57ba6ab4d7ba31bf6522b80159f2021-04-24T05:49:32ZengElsevierJournal of Lipid Research0022-22751973-07-01144446458Metabolic fate of rat and human lipoprotein apoproteins in the ratShlomo Eisenberg0Herbert G. Windmueller1Robert I. Levy2Laboratory of Nutrition and Endocrinology, National Institute of Arthritis, Metabolism, and Digestive Diseases, and Molecular Disease Branch, National Heart and Lung Institute, National Institutes of Health, Bethesda, Maryland 20014Laboratory of Nutrition and Endocrinology, National Institute of Arthritis, Metabolism, and Digestive Diseases, and Molecular Disease Branch, National Heart and Lung Institute, National Institutes of Health, Bethesda, Maryland 20014Laboratory of Nutrition and Endocrinology, National Institute of Arthritis, Metabolism, and Digestive Diseases, and Molecular Disease Branch, National Heart and Lung Institute, National Institutes of Health, Bethesda, Maryland 20014The fate of 125I-labeled apolipoproteins was studied in vivo in rats that had received intravenous injections of 125I-labeled rat HDL and 125I-labeled human HDL, LDL, and VLDL.Plasma decay curves of rat and human HDL were exponential with similar half-lives in the circulation (11–12 hr). After injection, low molecular weight apolipoproteins (apoLP-alanine of human HDL and fraction HS-3 of rat HDL) were found to redistribute to other lipoproteins, predominantly VLDL. Decay curves of individual HDL proteins were constructed after lipoprotein fractionation, delipidation, and polyacrylamide gel electrophoresis. It was found that the half-lives of the different HDL apoproteins were not identical. A major rat HDL protein (52% of total counts) had a circulating half-life (t½) of 12.5 hr. Two others had a t½ of 8–9 hr while the t½ of several others was 11–12 hr. The t½ of three well-characterized human HDL apoproteins, apoLP-glutamine I, apoLP-glutamine II, and apoLP-alanine, were 13.5, 9.0, and 15.0 hr, respectively.The fate of 125I-labeled human VLDL and LDL apoproteins in rats was similar to that described previously in humans. After injection of 125I-labeled human VLDL into rats, apoLP-glutamic acid and apoLP-alanine rapidly transferred to rat HDL and were lost thereafter from the circulation from both VLDL and HDL. The apoLDL moiety of human VLDL moved metabolically to the LDL density range (d = 1.019–1.063) through a lipoprotein of intermediate density (d = 1.006–1.019).Analysis of tissue radioactivity at time intervals after the injection of labeled lipoproteins suggests that the liver may play an important role in the clearance of all lipoprotein preparations from plasma.http://www.sciencedirect.com/science/article/pii/S0022227520368784lipoprotein turnoverlipoprotein catabolismhepatic lipoprotein catabolismiodinated lipoproteins |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Shlomo Eisenberg Herbert G. Windmueller Robert I. Levy |
spellingShingle |
Shlomo Eisenberg Herbert G. Windmueller Robert I. Levy Metabolic fate of rat and human lipoprotein apoproteins in the rat Journal of Lipid Research lipoprotein turnover lipoprotein catabolism hepatic lipoprotein catabolism iodinated lipoproteins |
author_facet |
Shlomo Eisenberg Herbert G. Windmueller Robert I. Levy |
author_sort |
Shlomo Eisenberg |
title |
Metabolic fate of rat and human lipoprotein apoproteins in the rat |
title_short |
Metabolic fate of rat and human lipoprotein apoproteins in the rat |
title_full |
Metabolic fate of rat and human lipoprotein apoproteins in the rat |
title_fullStr |
Metabolic fate of rat and human lipoprotein apoproteins in the rat |
title_full_unstemmed |
Metabolic fate of rat and human lipoprotein apoproteins in the rat |
title_sort |
metabolic fate of rat and human lipoprotein apoproteins in the rat |
publisher |
Elsevier |
series |
Journal of Lipid Research |
issn |
0022-2275 |
publishDate |
1973-07-01 |
description |
The fate of 125I-labeled apolipoproteins was studied in vivo in rats that had received intravenous injections of 125I-labeled rat HDL and 125I-labeled human HDL, LDL, and VLDL.Plasma decay curves of rat and human HDL were exponential with similar half-lives in the circulation (11–12 hr). After injection, low molecular weight apolipoproteins (apoLP-alanine of human HDL and fraction HS-3 of rat HDL) were found to redistribute to other lipoproteins, predominantly VLDL. Decay curves of individual HDL proteins were constructed after lipoprotein fractionation, delipidation, and polyacrylamide gel electrophoresis. It was found that the half-lives of the different HDL apoproteins were not identical. A major rat HDL protein (52% of total counts) had a circulating half-life (t½) of 12.5 hr. Two others had a t½ of 8–9 hr while the t½ of several others was 11–12 hr. The t½ of three well-characterized human HDL apoproteins, apoLP-glutamine I, apoLP-glutamine II, and apoLP-alanine, were 13.5, 9.0, and 15.0 hr, respectively.The fate of 125I-labeled human VLDL and LDL apoproteins in rats was similar to that described previously in humans. After injection of 125I-labeled human VLDL into rats, apoLP-glutamic acid and apoLP-alanine rapidly transferred to rat HDL and were lost thereafter from the circulation from both VLDL and HDL. The apoLDL moiety of human VLDL moved metabolically to the LDL density range (d = 1.019–1.063) through a lipoprotein of intermediate density (d = 1.006–1.019).Analysis of tissue radioactivity at time intervals after the injection of labeled lipoproteins suggests that the liver may play an important role in the clearance of all lipoprotein preparations from plasma. |
topic |
lipoprotein turnover lipoprotein catabolism hepatic lipoprotein catabolism iodinated lipoproteins |
url |
http://www.sciencedirect.com/science/article/pii/S0022227520368784 |
work_keys_str_mv |
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