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Literature DB >> 6929548

Unreliability of tritiated cholesterol: studies with [1,2-3H]-cholesterol and [24,25-3H]cholesterol in humans.

N O Davidson, E H Ahrens, H L Bradlow, D J McNamara, T S Parker, P Samuel.

Abstract

Over the past 18 months different lots of [1,2-3H]cholesterol and [24,25-3H]cholesterol were found to be radiochemically acceptable by conventional chemical and other in vitro tests, yet, when co-administered with [4-14C]cholesterol to human subjects, an abrupt fall in the 3H/14C specific activity ratio in plasma cholesterol was discovered in every case. We have concluded that all batches of [3H]cholesterol should be regarded as radiochemically unreliable unless they are shown to behave identically in all respects to [4-14C]cholesterol in an appropriate in vivo assay system.

Entities: Chemical Species

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Year: 1980 PMID： 6929548 PMCID： PMC348692 DOI： 10.1073/pnas.77.4.2255

Source DB: PubMed Journal: Proc Natl Acad Sci U S A ISSN： 0027-8424 Impact factor: 11.205

21 in total

1. A simple and precise assay of the enzymatic conversion of cholesterol into pregnenolone.

Authors: R B Hochberg; M Welch; S Lieberman
Journal: Biochemistry Date: 1974-01-29 Impact factor: 3.162

2. Improved separation of sterols by reversed-phase thin-layer chromatography.

Authors: N J De Souza; W R Nes
Journal: J Lipid Res Date: 1969-03 Impact factor: 5.922

3. Effect of tritium labeling of cortisol on its physical-chemical properties and on its metabolism in man.

Authors: N I Gold; J F Crigler
Journal: J Clin Endocrinol Metab Date: 1966-02 Impact factor: 5.958

4. An evaluation of four methods for measuring cholesterol absorption by the intestine in man.

Authors: E Quintão; S M Grundy; E H Ahrens
Journal: J Lipid Res Date: 1971-03 Impact factor: 5.922

5. Synthesis of 3 -hydroxy- 5 -steroids by sodium borohydride reduction of dienol trimethylsilyl ether derivatives of 3-oxo- 4 -steroids.

Authors: L Aringer; P Eneroth
Journal: Steroids Date: 1971-10 Impact factor: 2.668

6. Measurements of cholesterol turnover, synthesis, and absorption in man, carried out by isotope kinetic and sterol balance methods.

Authors: S M Grundy; E H Ahrens
Journal: J Lipid Res Date: 1969-01 Impact factor: 5.922

7. Synthesis of (1,2- 3 H 2 )cholecalciferol and metabolism of (4- 14 C,1,2- 3 H 2 )- and (4- 14 C,1- 3 H)-cholecalciferol in rachitic rats and chicks.

Authors: D E Lawson; B Pelc; P A Bell; P W Wilson; E Kodicek
Journal: Biochem J Date: 1971-02 Impact factor: 3.857

Unreliability of tritiated cholesterol: studies with [1,2-3H]-cholesterol and [24,25-3H]cholesterol in humans.

1. A simple and precise assay of the enzymatic conversion of cholesterol into pregnenolone.

2. Improved separation of sterols by reversed-phase thin-layer chromatography.

3. Effect of tritium labeling of cortisol on its physical-chemical properties and on its metabolism in man.

4. An evaluation of four methods for measuring cholesterol absorption by the intestine in man.

5. Synthesis of 3 -hydroxy- 5 -steroids by sodium borohydride reduction of dienol trimethylsilyl ether derivatives of 3-oxo- 4 -steroids.

6. Measurements of cholesterol turnover, synthesis, and absorption in man, carried out by isotope kinetic and sterol balance methods.

7. Synthesis of (1,2- 3 H 2 )cholecalciferol and metabolism of (4- 14 C,1,2- 3 H 2 )- and (4- 14 C,1- 3 H)-cholecalciferol in rachitic rats and chicks.

8. 1,2-3-H cholesterol as a tracer in studies of human cholesterol metabolism.

9. The stereospecificity of tritium distribution in [1-3H]- and [1,2-3H2]-cholesterol and -cholecalciferol.

10. Turnover of plasma cholesterol in man.

1. Microscale preparation of natural and labeled oxysterols.

2. Heterogeneity of cholesterol homeostasis in man. Response to changes in dietary fat quality and cholesterol quantity.

3. In vivo influx of free and esterified plasma cholesterol into human aortic tissue without atherosclerotic lesions.