scholarly journals The synthesis of bile acids in perfused rat liver subjected to chronic biliary drainage

1970 ◽  
Vol 118 (3) ◽  
pp. 519-530 ◽  
Author(s):  
I. W. Percy-Robb ◽  
G. S. Boyd
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Rat Liver ◽  
Chenodeoxycholic Acid ◽  
Biliary Drainage ◽  
Specific Radioactivity ◽  
Mevalonic Acid ◽  
Liver Cholesterol ◽  
Microscopic Appearance

1. Isolated rat liver was perfused with heparinized whole blood under physiological pressure resulting in the secretion of bile at about the rate observed in vivo. 2. The preparation remained metabolically active for 4h and was apparently normal in function and microscopic appearance. 3. When the perfusate plasma and liver cholesterol pool was labelled by the introduction of [2-14C]mevalonic acid the specific radioactivity of the perfusate cholesterol increased. The biliary acids (cholic acid and chenodeoxycholic acid) were labelled and had the same specific radioactivity. 4. Livers removed from rats immediately after, and 40h after, the start of total biliary drainage, were perfused; increased excretion rates of both cholic acid and chenodeoxycholic acid were found when the liver donors had been subjected to biliary drainage. 5. The incorporation of [2-14C]mevalonic acid or rat lipoprotein labelled with [14C]cholesterol into bile acids was studied. 6. A dissociation between the mass of bile acid excreted and the rate of incorporation of 14C was found. This was attributed to the changing specific radioactivity of the cholesterol pool acting as the immediate bile acid precursor.

Radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid from human serum, with use of 125I-labeled ligands.

1979 ◽  
Vol 25 (2) ◽  
pp. 264-268 ◽  
Author(s):  
O Mäentausta ◽  
O Jänne
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Chenodeoxycholic Acid ◽  
Deoxycholic Acid ◽  
Serum Samples ◽  
Analytical Recovery ◽  
Hepatobiliary Diseases ◽  
Polyethylene Glycol Precipitation ◽  
Free Serum

Abstract We describe a method for radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid in serum. In the method, 125I-labeled bile acid conjugates are used as the tracers along with antibodies raised against individual bile acid-bovine serum albumin conjugates. Antibody-bound and free bile acids were separated by polyethylene glycol precipitation (final concentration, 125 g/L). Before radioimmunoassay, 0.1-mL serum samples were precipitated with nine volumes of ethanol, and portions from the supernate were used in the assays. The lowest measurable amounts of the bile acids, expressed as pmol/tube, were: cholic acid conjugates, 2; chenodeoxycholic acid conjugates, 0.5; and deoxycholic acid conjugates. 2. Analytical recovery of bile acids added to bile acid-free serum ranged from 85 to 110%; intra-assay and inter-assay CVs ranged from 3.2 to 5.3% and from 5.3 to 12.2%, respectively. Concentrations (mean +/- SD) of the bile acid conjugates in serum from apparently healthy women and men (in mumol/L) were: cholic acid conjugates, 0.43 +/- 0.17 (n = 126); chenodeoxycholic acid conjugates, 0.47 +/- 0.23 (n = 111); and deoxycholic acid conjugates, 0.33 +/- 0.11 (n = 96). The values for primary bile acids were greatly increased in patients with various hepatobiliary diseases.

scholarly journals Studies on the origin of biliary phospholipid. Effect of dehydrocholic acid and cholic acid infusions on hepatic and biliary phospholipids

1990 ◽  
Vol 270 (3) ◽  
pp. 691-695 ◽  
Author(s):  
F Chanussot ◽  
H Lafont ◽  
J Hauton ◽  
B Tuchweber ◽  
I Yousef
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Bile Flow ◽  
Normal Values ◽  
Specific Radioactivity ◽  
Regulatory Effect ◽  
Experimental Protocol ◽  
Dehydrocholic Acid ◽  
Cellular Organelles

The correlation between the secretion of biliary phospholipid (PL) and bile acid suggests a regulatory effect of bile acid on PL secretion. Bile acids may influence PL synthesis and/or the mobilization of a preformed PL pool. The objective of this study was to determine the contribution of these two sources to biliary PL, by using an experimental protocol in which dehydrocholic acid (DHCA) and cholic acid (CA) were infused to manipulate biliary PL secretion. In control rats, there was a steady state in bile flow. PL secretion and the biliary secretion of newly synthesized phosphatidylcholine (PC). The specific radioactivity of PC in bile was significantly higher than in plasma, microsomes and canalicular membranes. DHCA infusion decreased biliary PC secretion rate by 80%, and secretion returned to normal values at the transport maximum of CA. The specific radioactivity of biliary PC was decreased by 30% by DHCA infusion and reached normal values during CA infusion. There were no significant changes in the specific radioactivity of PC in plasma or cellular organelles during infusion of bile acids. These data indicate that: (1) newly synthesized PC contributes a small percentage to biliary PC; thus a preformed pool (microsomal and extrahepatic) is a major source of biliary PL; (2) the contribution of the extrahepatic pool to the biliary PL may be more important than the microsomal pool.

scholarly journals Preparation of the 3-monosulphates of cholic acid, chenodeoxycholic acid and deoxycholic acid

1976 ◽  
Vol 155 (2) ◽  
pp. 401-404 ◽  
Author(s):  
E S. Haslewood ◽  
G A. D. Haslewood
Keyword(s):  
Liver Disease ◽  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Chenodeoxycholic Acid ◽  
Deoxycholic Acid ◽  
Single Step ◽  
Acid Sulphate

1. The 3-sulphates of cholic, chenodeoxycholic and deoxycholic acids were prepared as crystalline disodium salts. 2. The method described shows that it is possible to prepare specific sulphate esters of polyhydroxy bile acids and to remove protecting acyl groups without removing the sulphate. 3. A study of bile acid sulphate solvolysis showed that none of the usual methods give the original bile acid in major yield in a single step. 4. An understanding of the preparation, properties and methods of solvolysis of bile acid sulphates is basic for investigations of cholestasis and liver disease.

scholarly journals Nuclear and cytosolic distribution of conjugated cholic acid and radiolabelled glycocholic acid in rat liver

1979 ◽  
Vol 178 (1) ◽  
pp. 71-78 ◽  
Author(s):  
R C Strange ◽  
G J Beckett ◽  
I W Percy-Robb
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Rat Liver ◽  
Superior Mesenteric Vein ◽  
Acid Synthesis ◽  
Bile Acid Synthesis ◽  
Acid Receptor ◽  
Glycocholic Acid ◽  
Bile Acid Receptor

1. Normally fed and cholestyramine-treated rats were injected through the superior mesenteric vein with different amounts of radiolabelled glycoholic acid and the appearance of radioactivity in bile was measured. 2. In normally fed rats radioactivity appeared in bile within 30 s of injection and reached a maximum after 2 1/2 min; in the cholestyramine-treated animals the appearance of radioactivity was slower and less of the injected material was excreted into bile. 3. At 10 min after injection, livers were removed and the amounts of radioactive glycoholic acid and endogenous cholic acid conjugates in nuclei and cytosol were determined; most of the bile acid was found in the cytosol, only small amounts being found in nuclei. 4. Nuclear preparations from both normally fed and cholestyramine-fed rats were extracted with KCl (0.4 M) in an attempt to identify a putative bile acid receptor, but no such receptor was found. 5. Regulation of bile acid synthesis does not involve nuclear binding of bile acids.

Influence of Deoxycholic Acid Feeding on the Elimination of Cholesterol in Normolipaemic Subjects

1974 ◽  
Vol 47 (5) ◽  
pp. 425-433
Author(s):  
K. Einarsson ◽  
K. Hellström ◽  
M. Kallner
Keyword(s):  
Bile Acid ◽  
Total Synthesis ◽  
Bile Acids ◽  
Cholic Acid ◽  
Chenodeoxycholic Acid ◽  
Deoxycholic Acid ◽  
Cholesterol Metabolism ◽  
Pool Size ◽  
Faecal Excretion ◽  
The Mean

1. The turnover of [24−14C]cholic acid and [3H]chenodeoxycholic acid and the faecal excretion of neutral steroids were studied in six normolipaemic subjects before and during the ingestion of 1.3–2.6 mmol (0.5–1.0 g) of deoxycholic acid/day. Before the second study the subjects had been fed deoxycholic acid for 2 weeks. 2. The administration of deoxycholic acid did not appear to influence cholesterol metabolism as judged by the absence of change in the serum concentrations and the overall transformation into primary bile acids and neutral faecal steroids. 3. During the deoxycholic acid feeding period the mean total synthesis of bile acids was reduced by about 30%, corresponding to approximately 0.25 mmol (100 mg)/day. In one subject the pool size and in another the synthesis of cholic acid remained unchanged; otherwise the cholic acid pool size and its rate of formation decreased in all subjects. No consistent effects were observed with regard to the turnover of chenodeoxycholic acid. 4. Assuming that the bile acid turnover is equivalent to bile acid excretion then the total amount of cholesterol eliminated as bile acids and neutral faecal steroids averaged between 1.6 and 1.8 mmol/day before and during the administration of deoxycholic acid.

Effects of bile acids on fecal excretion of end products of cholesterol metabolism

1960 ◽  
Vol 199 (4) ◽  
pp. 736-740 ◽  
Author(s):  
William T. Beher ◽  
Gizella D. Baker ◽  
William L. Anthony
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Cholesterol Metabolism ◽  
Fecal Excretion ◽  
Liver Cholesterol ◽  
Hyodeoxycholic Acid ◽  
End Products ◽  
Tissue Cholesterol ◽  
Steroid Excretion

The influence of bile acids on liver cholesterol mobilization and on the excretion of fecal end products of cholesterol-4-C14 metabolism was studied in mice. Tissue cholesterol was elevated by feeding a fat-free diet containing cholesterol or cholesterol-4-C14. The mice were then divided into three groups: cholic acid treated, control and hyodeoxycholic acid treated. Fecal collections were made at intervals for 20 days, and steroids extracted and fractionated. The quantity of the sterol fractions and the C14 activity of the sterol and bile acid fractions were determined. Regression of hepatic cholesterol was followed at the same time intervals. Cholic acid inhibited liver cholesterol mobilization, while hyodeoxycholic acid effected a rapid regression of liver cholesterol to subnormal levels. Cholic acid depressed total steroid excretion, the depression occurring in the bile acid fraction; while excretion of fecal sterols remained relatively unaltered. Hyodeoxycholic acid greatly increased total steroid excretion. The increase was in the sterol fraction (95%), while bile acid excretion was depressed. These data indicate that bile acids are important factors in determining the rate and route of cholesterol metabolism.

Changes in the pattern of bile acids in the nuclei of rat liver cells during hepatocarcinogenesis

2002 ◽  
Vol 102 (2) ◽  
pp. 143-150 ◽  
Author(s):  
M.E. MENDOZA ◽  
M.J. MONTE ◽  
M.Y. EL-MIR ◽  
M.D. BADIA ◽  
J.J.G. MARIN
Keyword(s):  
Bile Acid ◽  
Ursodeoxycholic Acid ◽  
Bile Acids ◽  
Cholic Acid ◽  
Rat Liver ◽  
Bile Acid Pool ◽  
Adult Rats ◽  
Isolated Nuclei ◽  
Acid Pool ◽  
Liver Homogenates

Bile acids reach the nuclei of hepatocytes, where they may play an important role in controlling gene expression by binding to nuclear receptors. In previous studies, changes in the amounts of the different molecular species of bile acids in the hepatocyte nucleus during rat liver regeneration have been reported. The aim of the present work was to investigate whether this also occurs during rat hepatocarcinogenesis. Liver cell nuclei were isolated after homogenization of livers from healthy adult rats (controls) and from rats at different time points during chemically induced hepatocarcinogenesis, corresponding to the stages of foci (12 weeks), hepatoma (20 weeks) and carcinoma (32 weeks). Bile samples from the cannulated common bile duct were collected for 1h from different sets of animals undergoing hepatocarcinogenesis. Bile acids in bile, liver homogenates and isolated nuclei were measured by GC-MS. Because the yield of nuclei isolated changed during the course of hepatocarcinogenesis (control, 20.1%; 12 weeks, 23.6%; 20 weeks, 7.8%; 32 weeks, 5.1%), amounts of bile acids in nuclei were corrected for the amount of DNA in each preparation. During hepatocarcinogenesis, bile acid concentrations in liver homogenates were reduced to approximately half the values obtained in control livers, while the levels of bile acids in both isolated nuclei and bile were not decreased. Hepatocarcinogenesis induced changes in the composition of bile acid pools. These were manifest as an increase in the proportion of cholic acid and a decrease in that of ursodeoxycholic acid in both bile and liver. These modifications differed from the changes seen in the nuclear bile acid pool, where a decrease in the proportion of cholic acid together with an increase in that of ursodeoxycholic acid were the major changes observed during hepatocarcinogenesis. With regard to the ‘flat’ bile acids (allo-cholic acid plus Δ5- or Δ4-unsaturated bile acids), a marked hepatocarcinogenesis-induced increase in the output of these species in bile was found. However, these bile acids were only found in liver homogenates at the hepatoma stage, whereas they were not detected in isolated nuclei at any stage of hepatocarcinogenesis. In summary, these results support the existence of a bile acid pool in hepatocyte nuclei whose composition differs from that of the extranuclear bile acid pool. Moreover, they indicate that, during hepatocarcinogenesis, the composition of the nuclear pool undergoes important alterations.

Metabolism of 4-C14-cholesterol in the isolated perfused rat liver

1962 ◽  
Vol 202 (4) ◽  
pp. 699-703 ◽  
Author(s):  
Henry Danielsson ◽  
William Insull ◽  
Paul Jordan ◽  
Ove Strand
Keyword(s):  
Bile Acids ◽  
Rat Liver ◽  
Chenodeoxycholic Acid ◽  
Liver Cholesterol ◽  
Tween 20 ◽  
Isolated Perfused Rat Liver ◽  
Perfused Rat Liver ◽  
Mode Of Administration ◽  
Ethanol Extracts

The influence of the mode of administration on the distribution and oxidation of 4-C14-cholesterol in the isolated perfused rat liver has been studied. When labeled cholesterol was added to the perfusate as an emulsion with Tween 20 only about 1% of the labeled liver cholesterol was oxidized to bile acids. Approximately the same oxidation (1–2%) was obtained in perfusions of livers from animals injected with emulsions of 4-C14-cholesterol 1 hr before operation. When livers were perfused with blood withdrawn from animals injected with emulsions of 4-C14-cholesterol 24 hr prior to sacrifice the amount of labeled liver cholesterol converted to bile acids was about 10%, i.e., five to ten times more than in the above-mentioned sets of experiments, indicating the advisability of using physiological solutions of cholesterol rather than artificial emulsions. The main labeled acidic products were identified as cholic and chenodeoxycholic acid. The only labeled product isolated from ethanol extracts of the liver was found to be identical with cholesterol.

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