The use of polarography in the examination of ketosteroids related to cholesterol

Sterol Metabolism. I. 26-Hydroxycholesterol in the Human Aorta*

“…It must be emphasized that our detection of cholesta-3.5-dien-7-one in the present sterol fractions neither confirms nor denies the prior claims for its isolation from or detection in the human aorta (Hardegger et al, 1943;Kantiengar and Morton, 1955;Robertson, 1955), since our results apply here only to aortal polar sterol fractions initially more polar than cholesterol on column and thin layer chromatoplates. The ready dehydration of 7-ketocholesterol herein observed in relatively uncomplicated chromatographic procedures does support an artifact status for cholesta-3,5-dien-7-one recovered from tissues where controlled chromatographic observation of the several steps involved was not had.…”

“…Furthermore, the presence of desmosterol in aortal tissue of patients treated with triparanol has been reported (Blankenhorn et al, 1961;Hollander, 1961, 1965; Jose and Peak, 1963). Other sterols isolated from or detected in the human aorta include cholesta-3,5-dien-7- one (Hardegger et al, 1943;Kantiengar and Morton, 1955;Robertson, 1955), cholesta-4,6-dien-3-one (Hardegger et al, 1943;Robertson, 1955), 5a-cholestane-3/3,5,6/3-triol (Hardegger et al, 1943;Henderson and McDougall, 1954;Henderson, 1956), 7a-hydroxycholesterol (Hardegger et al, 1943;Henderson and McDougall, 1954; Henderson, 1956), 7/3-hydroxycholesterol (Henderson, 1956), 24or 25-hydroxycholesterol (Henderson, 1956), and 7-ketocholesterol (Schoenheimer, 1932;Brooks et al, 1966). More recently 26-hydroxycholesterol has been detected as a constituent of human atherosclerotic plaques (Steel et al, 1966;Brooks et al, 1966) and cholesteryl sulfate has been isolated from human aortal tissue (Drayer and Lieberman, 1967).…”

Pharmaceuticals and Related Drugs

“…Barbituric acid derivatives produce an intense red-violet color with copper-pvridine reagent (256). Barbiturates can be titrated in a chloroform-polyethylene glycol 400 solvent system using sodium methoxide in methanol as titrant (488). Color reactions of thiobarbituric acid derivatives were reported (209) as W'ell as quantitative methods (549) for their determination.…”