Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs.
Previous studies have shown that treatment of guinea pigs with lovastatin alters the composition and the metabolic properties of circulating low density lipoprotein (LDL). Specifically, LDL isolated from lovastatin-treated animals is cleared from plasma more slowly than LDL isolated from control ani...
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Format: | Article |
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Elsevier
1994-06-01
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Series: | Journal of Lipid Research |
Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227520401105 |
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author | L F Berglund W F Beltz R L Elam J L Witztum |
author_facet | L F Berglund W F Beltz R L Elam J L Witztum |
author_sort | L F Berglund |
collection | DOAJ |
description | Previous studies have shown that treatment of guinea pigs with lovastatin alters the composition and the metabolic properties of circulating low density lipoprotein (LDL). Specifically, LDL isolated from lovastatin-treated animals is cleared from plasma more slowly than LDL isolated from control animals, when injected into the guinea pig. In the present study, we examine whether lovastatin also affects the metabolic properties of very low density lipoprotein (VLDL), the metabolic precursor of LDL. VLDL isolated from lovastatin-treated guinea pigs (L-VLDL) and VLDL isolated from untreated (control) guinea pigs (C-VLDL) were radioiodinated and simultaneously injected into eight untreated guinea pigs. Radioactivity associated with apolipoprotein B-100 (apoB) was measured in four plasma density fractions and analyzed using a compartmental model consisting of fast and slow pools for VLDL, fast and slow pools for intermediate density lipoprotein (IDL), and a single slow pool for LDL. The fractional catabolic rate (FCR) for C-VLDL apoB was 2.8 +/- 1.0 h-1 and for L-VLDL apoB was 5.1 +/- 2.0 h-1 (P < 0.002, paired t test). The fractions of control and lovastatin VLDL apoB converted to LDL averaged 0.15 +/- 0.15 and 0.02 +/- 0.02, respectively (P < 0.05, paired t test). Finally, the FCRs of LDL apoB derived from control and lovastatin VLDL were similar (0.059 +/- 0.007 h-1 and 0.083 +/- 0.038 h-1, respectively; paired t test not significant). These data indicate that L-VLDL was irreversibly removed from the plasma of an untreated guinea pig more rapidly than was C-VLDL. Thus, the metabolic behavior of VLDL apoB is affected by lovastatin. Therefore, changes in lipoprotein particles themselves must be considered in assessing the overall impact of treatment with lovastatin. |
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spelling | doaj.art-91eda47e31d94e64a44a6f606dfb70f02022-12-21T21:56:34ZengElsevierJournal of Lipid Research0022-22751994-06-01356956965Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs.L F Berglund0W F Beltz1R L Elam2J L Witztum3Department of Medicine, University of California, San Diego, La Jolla 92093-0682.Department of Medicine, University of California, San Diego, La Jolla 92093-0682.Department of Medicine, University of California, San Diego, La Jolla 92093-0682.Department of Medicine, University of California, San Diego, La Jolla 92093-0682.Previous studies have shown that treatment of guinea pigs with lovastatin alters the composition and the metabolic properties of circulating low density lipoprotein (LDL). Specifically, LDL isolated from lovastatin-treated animals is cleared from plasma more slowly than LDL isolated from control animals, when injected into the guinea pig. In the present study, we examine whether lovastatin also affects the metabolic properties of very low density lipoprotein (VLDL), the metabolic precursor of LDL. VLDL isolated from lovastatin-treated guinea pigs (L-VLDL) and VLDL isolated from untreated (control) guinea pigs (C-VLDL) were radioiodinated and simultaneously injected into eight untreated guinea pigs. Radioactivity associated with apolipoprotein B-100 (apoB) was measured in four plasma density fractions and analyzed using a compartmental model consisting of fast and slow pools for VLDL, fast and slow pools for intermediate density lipoprotein (IDL), and a single slow pool for LDL. The fractional catabolic rate (FCR) for C-VLDL apoB was 2.8 +/- 1.0 h-1 and for L-VLDL apoB was 5.1 +/- 2.0 h-1 (P < 0.002, paired t test). The fractions of control and lovastatin VLDL apoB converted to LDL averaged 0.15 +/- 0.15 and 0.02 +/- 0.02, respectively (P < 0.05, paired t test). Finally, the FCRs of LDL apoB derived from control and lovastatin VLDL were similar (0.059 +/- 0.007 h-1 and 0.083 +/- 0.038 h-1, respectively; paired t test not significant). These data indicate that L-VLDL was irreversibly removed from the plasma of an untreated guinea pig more rapidly than was C-VLDL. Thus, the metabolic behavior of VLDL apoB is affected by lovastatin. Therefore, changes in lipoprotein particles themselves must be considered in assessing the overall impact of treatment with lovastatin.http://www.sciencedirect.com/science/article/pii/S0022227520401105 |
spellingShingle | L F Berglund W F Beltz R L Elam J L Witztum Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs. Journal of Lipid Research |
title | Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs. |
title_full | Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs. |
title_fullStr | Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs. |
title_full_unstemmed | Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs. |
title_short | Altered apolipoprotein B metabolism in very low density lipoprotein from lovastatin-treated guinea pigs. |
title_sort | altered apolipoprotein b metabolism in very low density lipoprotein from lovastatin treated guinea pigs |
url | http://www.sciencedirect.com/science/article/pii/S0022227520401105 |
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