Diurnal variations of plasma lipids, tissue and plasma lipoprotein lipase, and VLDL secretion rates in the rat. A model for studies of VLDL metabolism

Patrizia Marrino*, Dov Gavish, Eleazar Shafrir, Shlomo Eisenberg

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Circadian rhythms of plasma lipids and lipoproteins, lipoprotein lipase activities and VLDL secretion rates were studied in fed and food-deprived (12 h) male rats after a light/dark synchronization of 14 days. In ad libitum fed rats, a circadian rhythm of plasma triacylglycerol, blood glucose and liver glycogen was clearly identified. A rhythm was also identified for plasma cholesterol, but not phospholipids. The peak of plasma triacylglycerol occurred 2 h after the beginning of the light period (7.00 a.m.), and the nadir, 2 h after the beginning of the dark period (7.00 p.m.). The differences of plasma triacylglycerol at these two circadian stages were even more pronounced in food-deprived rats and were confined to the very-low-density lipoprotein (VLDL) fraction. Plasma post-heparin and heart and muscle lipoprotein lipase activities were 50-100% higher at 7.00 p.m., the time when plasma triacylglycerol were lowest, as compared to 7.00 a.m. Plasma post-heparin hepatic lipase and adipose tissue lipoprotein lipase activities, in contrast, did not change. VLDL secretion rates were somewhat higher at 7.00 a.m. compared to 7.00 p.m., but this difference was not significant. It is concluded that physiological variation of heart and muscle lipoprotein lipase together with small differences of VLDL secretion rates are responsible for normal range oscillations of plasma VLDL triacylglycerol levels.

Original languageEnglish
Pages (from-to)277-284
Number of pages8
JournalBiochimica et Biophysica Acta - Molecular and Cell Biology of Lipids
Volume920
Issue number3
DOIs
StatePublished - 15 Aug 1987
Externally publishedYes

Keywords

  • (Rat)
  • Diurnal variation
  • Lipoprotein lipase
  • Lipoprotein metabolism Plasma lipid level
  • Triacylglycerol
  • VLDL secretion

Fingerprint

Dive into the research topics of 'Diurnal variations of plasma lipids, tissue and plasma lipoprotein lipase, and VLDL secretion rates in the rat. A model for studies of VLDL metabolism'. Together they form a unique fingerprint.

Cite this