The catabolism of cholesterol in vitro. Formation of 3-alpha,7-alpha,12-alpha-trihydroxy-5-beta-cholestanoic acid from cholesterol by rat liver.
1. Both 25-d- and 25-l-3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoic acid were isolated from the gall-bladder bile of Crocodylus niloticus. 2. The catabolism of cholesterol to 25-d- and 25-l-3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoic acid respectively was studied by using a rat liver preparation in vitro. The results show that rat liver can metabolize cholesterol to both forms of 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoic acid. However, a preference was noted for the formation from [4-(14)C]cholesterol of 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoic acid (25-d), which was isolated from the incubations with a specific radioactivity about four times that of 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoic acid (25-l). 3. The results indicate that 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoic acid is a normal intermediate in the biosynthesis of bile acids from cholesterol in the rat.
D000818:Animals; D001646:Bile / Q000032:analysis; D001647:Bile Acids and Salts / Q000032:analysis / Q000096:biosynthesis; D002776:Cholestanes / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism*; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism*; D051381:Rats; D012104:Reptiles; D013261:Sterols / Q000096:biosynthesis / Q000302:isolation & purification
D001647:Bile Acids and Salts; D002776:Cholestanes; D013261:Sterols; D002784:Cholesterol