title: The effect of portacaval transposition of hepatic cholesterol-7alpha-hydroxylase activity in the rat.
abstract: Portacaval anastomosis in the rat results in an increase in the activity of the liver microsomal cholesterol-7alpha-hydroxylase enzyme system. The increase in the activity of this oxygenase occurs despite a decrease in the total amount of cytochrome p450 in the liver microsomes after portacaval anastomosis. It is possible to increase further the activity of the cholesterol-7alpha-hydroxylase enzyme in these portacaval shunted animals by feeding them on a diet containing a bile salt sequestering agent. This suggests that one of the factors influencing the activity of the liver microsomal cholesterol-7alpha-hydroxylase enzyme may be the concentration of bile salts reaching the liver from the blood plasma. Portacaval anastomosis in the rat tended to achieve a small decrease in the plasma cholesterol concentration.
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000378:metabolism; D002784:Cholesterol / Q000097:blood* / Q000378:metabolism; D002790:Cholesterol 7-alpha-Hydroxylase / Q000378:metabolism*; D002792:Cholestyramine Resin / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D008099:Liver / Q000033:anatomy & histology / Q000098:blood supply / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology* / Q000378:metabolism; D009929:Organ Size; D011167:Portacaval Shunt, Surgical; D051381:Rats; D013250:Steroid Hydroxylases / Q000378:metabolism*
chemical_list: D001647:Bile Acids and Salts; D002792:Cholestyramine Resin; D003577:Cytochrome P-450 Enzyme System; D002784:Cholesterol; D013250:Steroid Hydroxylases; D002790:Cholesterol 7-alpha-Hydroxylase