| Popis: |
3 beta-Hydroxy-25,26,26,26,27,27,27-heptafluoro-5 alpha-cholest-8(14)-en-15-one (VII), an analog of 3 beta-hydroxy-5 alpha-cholest-8(14)-en-15-one (I) in which conversion to 26- and 25-oxygenated metabolites is blocked by the F7-substitution, was administered to male Sprague-Dawley rats at levels of from 0.025 to 0.15% by weight in a ground chow diet. Administration of VII resulted in lowering of the levels of serum cholesterol at dosages as low as 0.025% by weight in diet. In marked contrast to I, VII had little or no effect on food consumption. Whereas administration of I at a level of 0.1% by weight in diet resulted in a cessation of growth, VII, at approximately the same molar concentration in diet, had only slight or no effect on changes in total body weight. Significant levels of 25,26,26,26,27,27,27-heptafluorocholesterol (VIII) were observed in serum and liver, indicating the conversion of VII to VIII. Characterization of VIII in liver was based upon the results of gas chromatography, low and high resolution mass spectral studies, infrared spectroscopy, and 1H and 13C nuclear magnetic resonance spectroscopy. The levels of VIII in serum appeared to be related to dosage and duration of administration of VII. |
