Biomaterial Database

Side-chain oxidation of lipoprotein-bound [24,25-3H]cholesterol in the rat: comparison of HDL and LDL and implications for bile acid synthesis. 1982

L K Miller, and M L Tiell, and I Paul, and T H Spaet, and R S Rosenfeld

The purpose of the study was to test the hypothesis that high density lipoprotein (HDL) cholesterol would be more easily oxidized in vivo than low density lipoprotein (LDL) cholesterol. Homologous plasma was incubated with [24,25-3H]cholesterol and fractionated by ultracentrifugation to obtain HDL and LDL each labeled with [3H] free sterol. HDL and LDL labeled with [24,25-3H]cholesteryl esters were prepared by ultracentrifugation of plasma from donor rats injected 24 hr previously with [24,25-3H]cholesterol in propylene glycol. These four labeled lipoproteins were administered to recipient rats. It was found that more tritium oxide (3H2O) was produced after the HDL doses than after the corresponding LDL doses, from 2--3-fold more when lipoprotein free cholesterol was labeled and from 2--6-fold more when lipoprotein cholesteryl esters were labeled. More 3H2O was produced from free cholesterol-labeled lipoproteins than from cholesteryl ester-labeled lipoproteins. Since oxidation of cholesterol is a measure of bile acid formation, it is concluded that under the conditions of the study HDL-cholesterol is a better precursor of bile acids than LDL-cholesterol.

UI	MeSH Term	Description	Entries
D008075	Lipoproteins, HDL	A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.	High Density Lipoprotein,High-Density Lipoprotein,High-Density Lipoproteins,alpha-Lipoprotein,alpha-Lipoproteins,Heavy Lipoproteins,alpha-1 Lipoprotein,Density Lipoprotein, High,HDL Lipoproteins,High Density Lipoproteins,Lipoprotein, High Density,Lipoprotein, High-Density,Lipoproteins, Heavy,Lipoproteins, High-Density,alpha Lipoprotein,alpha Lipoproteins
D008076	Cholesterol, HDL	Cholesterol which is contained in or bound to high-density lipoproteins (HDL), including CHOLESTEROL ESTERS and free cholesterol.	High Density Lipoprotein Cholesterol,Cholesterol, HDL2,Cholesterol, HDL3,HDL Cholesterol,HDL(2) Cholesterol,HDL(3) Cholesterol,HDL2 Cholesterol,HDL3 Cholesterol,alpha-Lipoprotein Cholesterol,Cholesterol, alpha-Lipoprotein,alpha Lipoprotein Cholesterol
D008077	Lipoproteins, LDL	A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.	Low-Density Lipoprotein,Low-Density Lipoproteins,beta-Lipoprotein,beta-Lipoproteins,LDL(1),LDL(2),LDL-1,LDL-2,LDL1,LDL2,Low-Density Lipoprotein 1,Low-Density Lipoprotein 2,LDL Lipoproteins,Lipoprotein, Low-Density,Lipoproteins, Low-Density,Low Density Lipoprotein,Low Density Lipoprotein 1,Low Density Lipoprotein 2,Low Density Lipoproteins,beta Lipoprotein,beta Lipoproteins
D008078	Cholesterol, LDL	Cholesterol which is contained in or bound to low density lipoproteins (LDL), including CHOLESTEROL ESTERS and free cholesterol.	LDL Cholesterol,Cholesteryl Linoleate, LDL,LDL Cholesteryl Linoleate,Low Density Lipoprotein Cholesterol,beta-Lipoprotein Cholesterol,Cholesterol, beta-Lipoprotein,beta Lipoprotein Cholesterol
D008297	Male		Males
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D002788	Cholesterol Esters	Fatty acid esters of cholesterol which constitute about two-thirds of the cholesterol in the plasma. The accumulation of cholesterol esters in the arterial intima is a characteristic feature of atherosclerosis.	Cholesterol Ester,Cholesteryl Ester,Cholesteryl Esters,Ester, Cholesterol,Ester, Cholesteryl,Esters, Cholesterol,Esters, Cholesteryl
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia