Sodium Dehydrocholate Research Articles

Glucose reabsorption from bile. Evidence for a biliohepatic circulation.

Glucose is absent from human bile and present in low concentrations in bile from the rat. To study the mechanisms of this blood-bile glucose concentration difference, infusions of glucose were administered i.v. to 300-400 g male Sprague-Dawley rats with ligated renal pedicles and to two postcholecystectomy patients with indwelling t-tubes. Glucose was assayed in plasma, bile, and rat liver by a hexokinase method specific for D-glucose. In man, glucose was detected in bile when plasma glucose increased above 350 mg/100 ml. In animals studies, low concentrations of bile glucose were observed at plasma levels between 100 and 300 mg/100 ml. However, when plasma concentrations increased between 400 and 900 mg/100 ml, glucose appeared more rapidly in bile, defining by extrapolation an apparent plasma glucose threshold of 280 mg/100 ml. Intraportal phlorizin, a competitive inhibitor of glucose transport, significantly increased bile glucose concentrations. Plasma-bile concentration differences were also observed in rats after i.v. [3-14C]O-methyl glucose (3-O-MG) but not after [3H]mannitol. Hepatic glucose levels were never lower than plasma levels and liver-plasma 3-O-MG ratios were 0.92 +/- 0.22 indicating that entry of glucose and 3-O-MG into hepatocyte water was not limiting. Furthermore, when sodium dehydrocholate augmented canalicular secretion, biliary glucose excretion increased proportionally suggesting that glucose entry into bile was not impeded. When estimates of hepatic glucose secretion were compared with biliary glucose excretion, the latter increased progressively when estimated secretion rates exceeded 50 micrograms/min or when phlorizin was given. Finally, during bile stop-flow experiments, [3-14C]O-MG and [14C]glucose were selectively removed from bile compared with [3H]mannitol. The findings suggest that glucose and 3-O-MG are reabsorbed from bile after entry at the hepatocyte, accounting for their low bile-plasma ratio. The biliary glucose transport process may be described by Michaelis-Menten kinetics and is analogous to recently defined kinetics for renal tubular reabsorption of glucose. These studies provide evidence that certain products of bile secretion may undergo a "biliohepatic" circulation.

The role of bile salts in the hepatic excretion of iopanoic acid.

Previous studies on the pharmacokinetics of iopanoic acid (Telepaque) have shown that there is a direct relationship between the biliary excretion of iopanoic acid and canalicular bile flow produced by bile salts (sodium taurocholate). The object of the present investigation is to determine if this association is due to an effect of canalicular bile flow per se or due to a direct action of bile salts. The role of micelle formation by bile salts in the transport process is also evaluated. Iopanoic acid excretion in bile was studied during choleresis produced by SC2644 (a compound which stimulates bile-salt independent canalicular bileflow), with sodium dehydrocholate (a bile salt which increases bile-salt dependent bile flow, but does not form micelles) and with sodium taurocholate (a micelle-forming bile-salt choleretic). Experiments were performed in both anesthetized dogs with a catheter placed in the common duct immediately prior to the experiment, and in nonanesthetized dogs prepared months earlier with a Thomas cannula inserted into the duodenum. The results show that the amount of iopanoic acid excreted in the bile rises in proportion to the increase in bile flow stimulated by dehydrocholate and taurocholate, but the total excretion remains unchanged by choleresis produced by SC2644. Failure of SC2644 to increase the excretion of iopanoic acid despite an increase in bile flow indicates that the canalicular bile flow per se is not the important determinant regulating iopanoic acid excretion. Because bile salts stimulate iopanoic acid excretion, it is the bile salts themselves and not the increase in bile flow that influence iopanoic acid. Since the experiments show no difference between the effect of dehydrocholate and taurocholate, it is not the micellar property of bile salts that enables these compounds to increase the rate of excretion of iopanoic acid. It is postulated that there is an allosteric interaction between bile salts and the carrier for iopanoic acid in the canalicular membrane which facilitates the transport of iopanoic acid from the hepatocyte into the bile.

Bile Salts: A Determinant of the Bile-Peritoneal Electrical Potential Difference in the Rat

The electrical potential difference (PD) between bile and peritoneal cavity of the rat was determined in order to obtain additional information concerning the mechanism of bile formation in this species. A significant negative PD (− 4.4 ± 0.6 mv) was measured in the basal state at a time when the rat was secreting normal amounts of bile salts. The intravenous administration of sodium dehydrocholate produced a significant increase in negative PD, bile salt concentration, bile salt output, and bile flow. When non-bile salt dependent canalicular secretion was studied by creating a biliary fistula, there was a marked fall in PD, bile salt concentration, and bile salt output, but only a modest decrease in bile flow. Although the genesis of the PD cannot be determined with certainty, these changes in electrical PD correlated best with changes in bile salt concentration; the PD fell toward zero when non-bile salt dependent canalicular secretion was predominant. If the measured PD reflects canalicular events, non-bile salt dependent canalicular secretion may be associated with zero PD in the rat.

Inhibition of Bilirubin Excretion in Man During Dehydrocholate Choleresis

Sodium dehydrocholate (Decholin, Dome Laboratories, West Haven, Conn.) was given intravenously to 5 fasting patients with external biliary drainage to determine its effect on bilirubin excretion. The range of bile flow for these patients during control periods was 0.31 to 0.44 ml per min, and for bile bilirubin concentrations was 25.9 to 57.6 mg per 100 ml. Bile bilirubin concentrations decreased to levels that were 8 to 18% of control values during the 60- to 70-min period after Decholin administration. In each patient the decrease in bile bilirubin concentration was greater than could be accounted for by the dilutional effect of increased bile water formation, and the rate of bilirubin excretion in bile diminished after Decholin administration. Studies with intravenously administered bilirubin-3H in 2 patients demonstrated that the cumulative recovery of label in bile was slower after giving Decholin, and the plasma disappearance rate of unconjugated bilirubin-3H was delayed. These data indicate that Decholin inhibits bilirubin excretion in man despite its choleretic effect.

Biliary excretion of lecithin and cholesterol in the dog.

The biliary excretion rates of bile acid, lecithin, and cholesterol were measured in unanesthetized dogs after interruption of enterohepatic circulation and during infusions of sodium taurocholate, sodium glycocholate, sodium dehydrocholate, SC2644 (a bicyclic organic acid with high choleretic potency), and secretin. Both lecithin output and cholesterol output were directly related to bile acid excretion rate. The curves describing these relationships were concave downward. Molar concentration ratios of lecithin-to-bile acid declined gradually from approximately 0.4 to 0.2 as bile acid output increased from approximately 1 to 70 mumoles/min. Cholesterol-to-lecithin molar ratios were highest (0.05-0.15) at very low rates of bile acid excretion, but descended rapidly to a plateau (0.03-0.04) which was constant over the entire range of bile acid excretion rates from 10 to 70 mumoles/min. Similar lipid excretion patterns were observed during glycocholate infusion, but secretin-induced choleresis and dehydrocholate-induced choleresis were unaccompanied by any increments in lecithin or cholesterol excretion and SC2644 (which caused a marked increase in canalicular bile production as measured by erythritol clearance) caused a depression of lipid excretion. The data are consistent with the view that lecithin moves passively from cell membranes to intracanalicular micelles, that transport of cholesterol is coupled to lecithin transport, and that there is also a small amount of independent passive transport of cholesterol from membranes to micelles. A model developed on these assumptions has been shown to behave in a fashion consistent with the entire range of these observations.

The influence of sodium dehydrocholate on the uptake of 3 H-desmethylphalloin by the perfused rat liver.

Sodium dehydrocholate diminished the uptake of3H-desmethylphalloin by the perfused rat liver. Only about 1% of the polypeptide was eliminated by bile.

Canalicular Bile flow and Bile Secretory Pressure: Evidence for a non-bile salt dependent fraction in the isolated perfused rat liver

The relationship between bile salt secretion, bile flow, and bile secretory pressure was examined in the isolated perfused rat liver during alternating infusions of saline and sodium taurocholate or sodium dehydrocholate. A large fraction of bile (1.25 μliter per min per g of liver) as well as bile secretory pressure was found to be independent of bile salt secretion. Since the biliary clearance of 14C-mannitol was closely related to the rate of bile production, the canaliculus was presumed to be the main source of bile in this system. These studies indicate a primary mechanism for the production of canalicular bile and bile secretory pressure which is independent of the biliary secretion of bile salts.

Bilirubin distribution studies in Gunn rats following the injection of sodium dehydrocholate.

Bilirubin distribution studies in Gunn rats following the injection of sodium dehydrocholate.

Bile flow in the rat after enteral administration of bile salts.

The effects of enteral administration of various bile salts on bile output were investigated in the rat. After intraduodenal administration, all bile salts significantly increased bile flow and total bile output. Dehydrocholate had the greatest effect on bile flow. Cholate was next in degree of effectiveness followed by taurocholate, deoxycholate, and taurodeoxycholate. Bile output was significantly lower after ileal or gastric intubation of sodium dehydrocholate or taurocholate than after duodenal administration of these compounds. Conjugation of the bile salts tended to depress the overall effect on bile flow. These effects are discussed in terms of possible differences in the absorption of conjugated and unconjugated bile salts. Comparison of the effects of sodium dehydrocholate and taurocholate after intraduodenal and intravenous or intraperitoneal administration suggests that absorption rate or efficiency of absorption markedly influences the intensity of apparent choleretic activity. A relationship was observed between the structure of the bile salt and bile flow stimulation: the triketo form was more effective than the trihydroxy form and that, in turn, was more effective than the dihydroxy form. This is difficult to explain in terms of differences in absorbability but is consistent with a choleresis mechanism involving osmotic pressure effects. At a dose of 100 µmoles, in the rat, dehydrocholate does not function simply as a hydrocholeretic agent. Nevertheless, on the basis of the relative amount (percent) of solids in stimulated bile, there are clear differences in the nature of the choleretic activity of dehydrocholate and cholate.

Substitution of Lipids with Bile Salts in the Formation of Thrombin

SummaryThe generation of thrombin was studied in an activating system consisting of purified thrombin zymogens, purified autoprothrombin C, purified Ac-globulin, lipid or bile salts, and calcium chloride. With the concentration of calcium ions and pH fixed, the effect of varying the other three procoagulants was studied. Bile salts were effective substitutes for lipids in a concentration where micelles form. The approximate effectiveness from highest to lowest was: conjugated sodium salt of taurocholic acid, sodium cholate, sodium deoxycholate. Sodium dehydrocholate was ineffective. Autoprothrombin C is the enzyme for thrombin formation. For accelerating its activity best results were obtained with the simultaneous presence of optimal concentrations of calcium ions, Ac-globulin and lipids or bile salts. Reducing any one of the three to zero concentration decreased the rate and yield of thrombin generation.The form in which the zymogen is used was found to be important. Prothrombin complex, DE AE-prothrombin and prethrombin were studied. Each substrate has its peculiar requirements for yielding thrombin. Prothrombin complex and DEAE-pro-thrombin activated far more rapidly and required 10 times less autoprothrombin C than prethrombin. The yield of thrombin from these substrates was also higher than from prethrombin. DE AE-prothrombin required the least amount of lipid. For the bile salts the required concentrations were nearly always the same from one substrate to another. To a certain extent Benadryl could also be substituted for lipids. In association with rapid thrombin generation from DE AE-prothrombin the Ac-globulin and autoprothrombin C Avere represented in approximately a 6:1 molar ratio. As compared with the weight of the enzyme large amounts of Ac-globulin and cholate were required.DE AE-prothrombin was readily made refractory to the two-stage analytical reagents with purified platelet factor 3 and calcium ions. Combinations of sodium cholate and phosphatidyl serine were also effective, but either one alone was ineffective.

Canalicular bile production in dogs.

Canalicular bile production in dogs.

The transport of 14C-neostigmine from plasma to bile

The transport of 14C-neostigmine from plasma to bile was investigated in the rat. After i.v. injection of 14C-neostigmine, approximately 0.8 per cent of the administered radioactivity was recovered from bile within 4 hr. Concurrent infusion ofglycopyrronium or oxyphenonium did not modify the biliary excretion of radioactivity. However choleresis, induced by infusion of sodium dehydrocholate, significantly increased the excretion of radioactivity; approximately 1.3 per cent of the dose was detected in bile within 4 hr. In other experiments the concentration of radioactivity in plasma, liver cells, and bile was determined 30 min after intravenous 14C-neostigmine. The concentration of radioactivity in liver cell water was 3–15 times that in bile and 23–59 times that of plasma. Although neostigmine was concentrated 5-fold during transfer from plasma to bile, it was concluded that passive mechanisms were responsible for both the entry of the drug into liver cells and for its excretion in bile.

Cholinesterase activities in the gustatory region of the rat tongue and their inhibition by bitter-tasting substances.

The localization of cholinesterase activity in the tongue of albino rats was histochemically demonstrated by the thiocholine technique of Koelle and Friedenwald, modified by Gomori. The taste nerve fibers innervating the taste buds in the vallate and fungiform papillae contained cholinesterase of both true and pseudo types, the former being predominant. The taste buds themselves failed to show definite cholinesterase activity. True and pseudo cholinesterases were also found in the different sensory nerve endings in the lingual papillae, in the subepithelial nerve plexus, in the motor end plates of the lingual muscle, and in the autonomic nerve fibers innervating the serous Ebner's gland, mucous Weber's gland and the arterioles. The cholinesterase activity in the taste bud areas was found to be in-hibited by several kinds of bitter-tasting substances, including quinine hydro-chloride, methantheline bromide, berberine hydrochloride, L-methylephedrine hydrochloride, phenobarbital sodium and sodium dehydrocholate. Among the bitter substances tested, only phenylthiocarbamide, a substance with dual taste reaction, failed to inhibit the cholinesterase. Sweet-tasting substances such as sucrose, sodium cycloheylsulfamate and saccharin sodium were all ineffective in inhibiting cholinesterase. It was suggested that the inhibition of cholinesterase activity in the vicinity of taste buds may be associated with the mechanism of bitter taste.

Plasma and urinary bilirubin after administration of sodium dehydrocholate to jaundiced patients.

Plasma and urinary bilirubin after administration of sodium dehydrocholate to jaundiced patients.

The effects of a bile-salt sodium dehydrocholate upon liver blood-flow in man.

The effects of a bile-salt sodium dehydrocholate upon liver blood-flow in man.

Slow infusion intravenous cholangiography.

A safe and effective intravenous Cholangiographie agent has been available to radiologists since the introduction in Europe of Biligrafin as a 20 per cent solution of sodium iodipamide in 1953 and its successor in this country, the methylglucamine salt Cholografin.2 Through the twelve-year period, 1953 to 1965, clinical investigators using the recommended 20 cc injection have published widely divergent results on the success of this contrast agent (1–6). In their review of the literature, Floch and Geffen (7) noted that the incidence of nonvisualization was as high as 34 per cent, but with improved patient selection and experience the degree of failure is generally in the 6 to 15 per cent range. The duct was satisfactorily visualized in 83.5 per cent of the 237 cases in their series. Wise (8) indicated in his monograph that, with proper patient selection based on preliminary liver function evaluation, successful visualization of the common duct in the cholecystectomized patient might be improved from his initial results of 89.1 per cent in 1,194 cases to almost 100 percent. Most recently, Edmunds (9) reported 81 per cent visualization in 139 cases. Attempts to improve visualization of the common bile duct in cholecystectomized patients by mechanical aids such as abdominal compression (10) or the induction of sphincter spasm with morphine (11) have been notably unsuccessful. Similarly, dosage increases have been of little value. Pahl (12) noted this in a clinical trial in 1954, and more recently Fischer (13) reported no significant increase in biliary iodine in experimental animals after the ad-ministration of higher doses of contrast agent. Normally, 6 to 18 per cent of the injected medium is excreted through the kidneys (14), and increased doses produce higher urinary rather than liver excretion values. Experimental and clinical attempts to alter mechanisms of excretion have also failed to improve visualization efficiency or radiopacity. Edling and Helander (15) maintained that duct opacification was improved by the renal tubular blocking agents, PAH and penditan, used separately or in combination, but this has not been substantiated (16), since iodipamide is excreted through the kidneys by glomerular filtration (14). Fischer (17) found no increase in biliary iodine in dogs by the blocking of renal tubular function with probenecid. He also noted no significant improvement in biliary iodine by stimulating liver excretion with cortisol, sodium dehydrocholate, and tri-iodothyronine. Dehydration or the combined use of oral and intravenous Cholangiographie agents also produced no quantitative improvement in bile duct iodine. Liver excretion of iodipamide is attributed to both its molecular structure and its albumin-binding affinity. Lasser et al. (18) were unable to improve biliary excretion of contrast medium in rabbits by priming with human serum albumin or lowering blood pH to increase protein-binding affmity.

Selenium metabolism: VI. Effect of arsenic on the excretion of selenium in the bile

Arsenic has been demonstrated to increase greatly the amount of selenium excreted in rat bile. This effect was seen with several forms of selenium and arsenic over a wide dose range. The large amounts of selenium in the bile of rats treated with arsenic were approximately equivalent to the decreases in the retention of selenium in the liver. Arsenic did not affect the amount of selenium in the gastrointestinal contents of cannulated animals. Administration of sodium dehydrocholate caused no changes in the distribution or biliary excretion of selenium in animals receiving only selenite even though bile flow was markedly enhanced. But in animals receiving both arsenite and selenite, dehydrocholate or certain other choleretics inhibited the usual increase in the biliary output of selenium brought about by arsenic. Much of the selenium in the bile of arsenized rats appeared to be in different stages of association with macromolecular material. The administration of unlabeled selenite significantly increased the amount of radioarsenic in rat bile.

Hydrocholeresis in rats undergoing hemorrhagic shock

The effects of 20% hemorrhage and sodium dehydrocholate on bile flow were determined in 25 rats. During the 110 min experimental period on each animal, determinations of blood pressure and normal bile flow were made and the effects of sodium dehydrocholate before and after hemorrhage were measured. Following the surgically controlled hemorrhage, the blood pressure was reduced 43.5% and the bile flow was reduced 24.7%. Sodium dehydrocholate caused a 130.6% increase in bile flow before hemorrhage and a 198.2% increase after hemorrhage when compared to the control periods prior to administration of the drug. It is concluded that hydrocholeresis as induced by sodium dehydrocholate is increased in the rat undergoing a 20% hemorrhage.

Circulation Time in the Aged

To the Editor:— The experience in circulation time measurements in the aged varies from author to author. In a recentJournalarticle, Circulation Time in the Aged, ( JAMA 183 :1037 [March 23] 1963) values up to 27 sec (mean, 19.5 sec) were found in normal men without roentgenologic evidence of cardiac enlargement or other objective sign of cardiac disease. In a recent study ( J Mount Sinai Hosp NY 30 :15, 1963) I employed the intravenous sodium dehydrocholate (Decholin) method to determine circulation time in a group of men and women with established coronary heart disease. Included in this study were 12 men, aged 69 to 73 (average, 71), showing circulation time values ranging from 14 to 22.5 sec (mean, 17 sec). The discrepancy between the mean values of 17 and 19.5 sec in the two studies referred to becomes all the more significant with the realization that in my own

Effect of various bile salts on the anticandidal activity of amphotericin B and gentian violet and on the anti-staphylococcal activity of neomycin.

A MIXTURE of bile salts contained in ‘Bacto Bile Salts’ (Difco) has been found capable of: (a) neutralizing the anti-candidal activity of a number of anti-mycotic agents including amphotericin B and gentian violet1; (b) potentiating the anti-staphylococcal activity of neomycin2; (c) effecting a mucin-like enhancement of intraperitoneal staphylococcal virulence for mice3. Considering the last, with the exception of sodium dehydrocholate, each salt contained in the bile salts mixture is capable of exerting this in vivo action4. Mucin, cholesterol and lecithin, which are present in unspecified amounts, also possess this same capability5. The work recorded here is concerned with the effectiveness of various bile salts as well as of mucin, cholesterol and lecithin on the first two in vitro activities already noted.