Preputial Gland Tumor Sterols III. A METABOLIC PATHWAY FROM LANOSTEROL TO CHOLESTEROL*? A. A. KANDUTSCH AND A. E. RUSSELL
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چکیده
Sterols which have been identified in a transplantable preputial gland tumor are lanosterol, 24,25-dihydrolanosterol, 4cr-methylAs-cholestenol, A’-cholestenol, 7-dehydrocholesterol, and cholesterol (preceding paper (2)). Arranged in the above sequence, they suggest a possible pathway for the conversion of lanosterol to cholesterol. The studies presented in this report of acetate incorporation into these sterols, and of the metabolism of the labeled sterols, provide evidence that the suggested pathway does operate.
منابع مشابه
Flux analysis of cholesterol biosynthesis in vivo reveals multiple tissue and cell-type specific pathways
Two parallel pathways produce cholesterol: the Bloch and Kandutsch-Russell pathways. Here we used stable isotope labeling and isotopomer analysis to trace sterol flux through the two pathways in mice. Surprisingly, no tissue used the canonical K-R pathway. Rather, a hybrid pathway was identified that we call the modified K-R (MK-R) pathway. Proportional flux through the Bloch pathway varied fro...
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Key Words: 14 15 Abbreviations: 16 BCA, bicinchoninic acid assay 17 DHCR24, 24 dehydrocholesterol reductase 18 DCM, dichloromethane 19 DMEM, Dulbecco's modified Eagle's medium 20 D 2 O, deuterium oxide 21 FCS, fetal calf serum 22 HS, horse serum 23 IA: isotopomer analysis 24 ISA, isotopomer spectral analysis 25 K-R, Kandutsch-Russell 26 LC, liquid chromatography 27 MeOH, methanol 28 MIDA, mass ...
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