Enzymatic sulfation of glycochenodeoxycholic acid by tissue fractions from adult hamsters

Using a radiometric assay with glycochenodeoxycholic acid as substrate, bile acid:3'-phosphoadenosine-5'-phosphosulfate sulfotransferase activity was found in 105,000 g supernatant fractions of liver, proximal intestine, and adrenal gland homogenates from adult hamsters. Optimum conditions for measurement of the hepatic enzyme were determined. In both male and female animals sulfation only occurred at the 7 alpha-position. Saturation analysis with glycohenodeoxycholic acid revealed that the higher activity observed in fractions from female compared to male hamsters was due to a 4-fold lower apparent Km (79 muM vs. 317 muM) for this bile acid in the females. The sulfation of glycohenodeoxycholic acid was competitively inhibited by glycolithocholic acid, chenodeoxycholic acid, and ursodeoxycholic acid. The data are consistent with the concept that sulfation of many, if not all, bile acids can occur in vivo.

Modification of D-galactosamine-induced liver injury in the rat by spironolactone

Spironolactone, a competitive inhibitor of mineralocorticoid effects on the distal tubule of the kidney, has recently been found to have other metabolic effects. In these studies, spironolactone (200mg/kg intraperitoneally) for 3 days was found to have a marked protective effect against the hepatotoxic effect of D-galactosamine (275 mg/kg) in rats. Further progress in defining the mechanism of protection from D-galactosamine hepatic necrosis by spironolactone will require assessment of effects of spironolactone on uridine nucleotide metabolism.

Psychological androgyny and fear of success

This study examined the relationship between psychological androgyny and fear of success for 128 female undergraduates who were administered the Bern Sex-role Inventory and a 29-item, self-report, fear of success scale. From performance on the inventory subjects were assigned to one of four sex-role categories: sex-typed, sex-reversed, androgynous, or indeterminate. Androgynous and sex-reversed females manifested significantly less fear of success than either sex-typed or indeterminate females. These findings suggest that psychological androgyny is associated with dealing effectively with possible perceived negative consequences of success.

Assessment of the plasma disappearance of cholyl'l14C-glycine as a test of hepatocellular disease

The plasma disappearance of a tracer dose of cholyl-l14C-glycine has been examined in 12 control subjects and in 32 patients with hepatocellular dysfunction. Simple analysis of the data did not detect hepatic dysfunction except in severe hepatocellular disease. The greatest degree of discrimination between normal subjects and patients with mild liver disease was obtained by taking the ratio of the plasma retention at 60 minutes to that at 10 minutes; it was similar to that obtained with serum gamma-glutamyl transferase. The two hour post-prandial plasma "total" bile acid concentration gave complete separation between the control subjects and patients with liver disease.

Rickets in adult cystic fibrosis with myopathy, pancreatic insufficiency and proximal renal tubular dysfunction

Rickets is reported in a 19 year old white man with cystic fibrosis in whom pancreatic and hepatic involvement was advanced. There was evidence of secondary hyperparathyroidism with proximal renal tubular acidosis, aminoaciduria, phosphaturia and hypophosphatemia. Treatment with oral pancreatic and parenteral vitamin D supplements led to full recovery of the rachitic syndrome and the proximal renal tubular dysfunction.

The role of tubular reabsorption in the renal excretion of bile acids

1. The renal excretion of bile acids was studied in an isolated rat kidney preparation perfused with a protein-free medium. 2. Tubular reabsorption exceeded 95% for both non-sulphated and sulphated bile acids at filtered loads of less than 30 nmol/min. 3. At low filtered loads the reabsorption of taurocholate and taurochenodeoxycholate was almost complete. Efficient reabsorption of taurochenodeoxycholate was maintained over a wider range of filtered loads than for taurocholate. These observations suggest that active transport may occur. 4. At high filtered loads saturation of reabsorption of taurocholate and taurochenodeoxycholate did not occur, which indicates that passive diffusion is involved in reabsorption. 5. Active proximal-tubular secretion of bile acids was not demonstrated in competition experiments with p-aminohippurate. 6. The fractional reabsorption of taurocholate, chenodeoxycholate 3,7-disulphate and chenodeoxycholate 7-monosulphate was decreased by the addition of taurochenodeoxycholate to the perfusate, so that their renal excretion was enhanced. This interaction between the bile acids for reabsorption may explain the different composition of bile acids in urine compared with that in plasma in cholestasis in man. 7. Conjugated bilirubin decreased the fractional reabsorption of both taurocholate and taurochenodeoxycholate at low filtered loads (less than 30 nmol/min) but not at high filtered loads (400 nmol/min).

A simplified procedure for the isolation of bile acids from serum based on a batch extraction with the non-ionic resin--Amberlite XAD-7

A simple and reproducible method using the non-ionic resin, Amberlite XAD-7, for the isolation of bile acids from serum by a batch procedure is described. Recoveries were greater than 95% for the non-sulphated bile acids and greater than 70% for the sulphate esters of bile acids. By using 1 g of resin, recoveries were independent of the mass (0.1-5 mumol) of the bile acid present. Up to 35 samples a day can be extracted without requiring dedication of the operator. When serum extracts were analysed by the 3alpha-hydroxysteroid dehydrogenase procedure for estimation of bile acids, virtually all the background fluorescence was eliminated. These extracts were also suitable for gas liquid chromatography, thin layer chromatography, and radioimmunoassay.

Bile acids in liver disease associated with inflammatory bowel disease

To investigate the possibility that bowel-related liver disease is due to accumulation of abnormal bile acids in the enterohepatic circulation, bile acids have been measured in gall-bladder bile and portal blood of patients with chronic bowel disease, none of whom had liver disease. There was no difference in the composition and concentration of bile acids in bile and portal blood compared with control patients. In a second study, serum bile acid composition and concentrations were similar in two groups of patients with liver disease, whether they had bowel disease or not. In a further study, post-prandial serum bile acid concentrations were not elevated in a group of patients with chronic bowel disease, making it unlikely that subcliical liver disease was present. No evidence has been found to support the hypothesis that bowel-related liver disease in man results from the action of abnormal bile acids.

Evidence for renal control of urinary excretion of bile acids and bile acid sulphates in the cholestatic syndrome

1. The bile acids and bile acid sulphates in the urine, serum and bile of eight cholestatic patients were studied quantitatively by gasliquid chromatography and gas-liquid chromoatography/mass spectrometry. 2. The primary bile acids (cholic acid and chenodeoxycholic acid) comprised on average 94% of the total bile acids in bile, 70% in the serum and 64% in urine. 3. The percentage composition of bile acids in bile was relatively constant and was not influenced by the degree of cholestasis. In contrast, in the serum only the primary bile acids were increased, the concentrations of the secondary bile acids (deoxycholic acid and lithocholic acid) and the minor bile acids remaining constant. 4. The data do not support the hypothesis that monohydroxy bile acids accumulate in cholestasis and are related to the pathogenesis of this syndrome. 5. The pattern of bile acid urinary excretion was similar to that in the serum. But in one patient, 3alpha, 7beta, 12alpha-trihydroxy-5beta-cholan-24-oic acid was a principal urinary bile acid, although very low concentrations of the compound were found in that patient's serum, suggesting that some of the minor bile acids in urine may originate by epimerization in the kidney. 6. In bile only a small proportion of the bile acids was sulphated (range 2.1-4.6%) and in serum the degree of sulphation was very variable (9-50%). However, in urine, sulphate esters accounted for a large proportion of the total bile acids (33-72%). 7. The output of bile acid sulphate in the urine was related to the urine total bile acid output but the serum concentration of bile acid sulphate remained relatively constant. Consequently, in contrast to the non-sulphated bile acids, whose renal clearance was relatively constant, the renal clearance of sulphated bile acids was directly related to the urine total bile acid output. This finding is inconsistent with the earlier hypothesis that their predominance in urine was due to a high renal clearance. It may indicate renal synthesis of some of the bile acid sulphates in the urine and/or inhibition of active renal tubular reabsorption of sulphated bile acids by non-sulphated bile acids.

Diagnositic value of serum bile acid estimations in liver disease

Bile acid concentrations were estimated enzymatically in fasting and postprandial (two-hour) serum samples from 18 normal subjects and 30 patients with histologically proven hepatobiliary disease. The serum bile acid concentration was less than 15 mumol/1 in normal subjects and did not increase postprandially. The fasting serum bile acid concentration was raised in 27 of the patients with hepatobiliary disease, and following a meal was outside the normal range in all 30 patients. Other liver function tests were abnormal less frequently. These results suggest that the estimation of serum bile acids in the postprandial state is a sensitive screening test of hepatobiliary disease. They should be of particular value in patients in whom liver disease is suspected but not proven, and in those recovering from liver disease, especially following therapy.