Bile Transport Research Articles

Immunohistochemical localization of Na+,K+-ATPase in human liver.

The localization of Na+, K+-ATPase in human liver was investigated on the light and electron microscopic levels by using anti-sera on the catalytic subunit of Na+, K+-ATPase in human kidney. α-subunit of Na+, K+-ATPase was extracted from the gel of SDS-PAGE as an immune antigen and injected into rabbits in order to produce the antibody. Under light microscopic examination, reaction products were recognized at the bile canalicular, lateral and sinusoidal membranes of hepatocytes and luminal membrane of biliary epithelial cells on the PLP (periodate-lysine-paraformaldehyde) fixed frozen sections. By ultrastructural observation, reaction products were also recognized at the bile canalicular membrane of hepatocytes and luminal membrane of biliary epithelial cells. These results suggest that Na+, K+-ATPase is responsible for bile formation and transport processes on these membranes.

Contractile activity of bile canaliculi: Contraction or collapse?

The discovery that bile canaliculi are capable of spontaneous contractile activity has led to their use in the investigation of the physiology of the liver cell. The contraction of a bile canaliculus is dependent on the network of actin, which is found in the pericanalicular region of the hepatocyte, and agents that inhibit actin filaments interfere with canalicular contraction. Injection of calcium directly into the cytoplasm of one hepatocyte of a cell pair results in contraction of the canaliculus. To determine whether the contractile activity of adjacent bile canaliculi was coordinated, calcium was injected into one cell of a group of three hepatocytes that formed two neighboring bile canaliculi. Calcium microinjection resulted in contraction of the bile canaliculus contiguous with the microinjected cell and was followed by a contraction of the second, adjacent canaliculus. These secondary contractions occurred after an interval of approximately 45 seconds. The finding that bile canalicular contractions are coordinated with contractions occurring in a sequential fashion supports the hypothesis that within the liver lobule, transport of bile within the canalicular network results from the coordinated contractions of the canaliculi. Rat hepatocytes, when isolated and maintained in primary culture, are capable of producing forceful contractions of their bile canaliculi, with contractions occurring on a regular basis once every 5.5 minutes. To determine whether the contraction of one bile canaliculus affected the contraction of a neighboring canaliculus, cinephotomicrographic studies of pairs of contiguous canaliculi were undertaken. The activity of 10 pairs of contiguous canaliculi, and 10 pairs of noncontiguous canaliculi which served as a control group, was recorded for a period of 12.5 hours at the rate of 1 frame every 15 seconds. Using frame-by-frame analysis of this period of observation, we determined the time of contraction of each of the canaliculi in the pairs. Cross-correlations were obtained for the contraction times of each of the 10 pairs of contiguous canaliculi and 10 control pairs. A peak in activity was found, with that peak occurring five frames 75 seconds from the midline, whereas the noncontiguous controls showed no correlation in contractile activity. This finding indicates that, when one bile canaliculus contracts, a neighboring canaliculus is likely to contract after an interval of 1.25 minutes. That there is coordination of contractile activity of bile canaliculi suggests that, within the intact liver lobule, ordered motility function of the bile canaliculi may facilitate bile flow.

Demonstration of a Transcellular Vesicle Pathway for Biliary Excretion of Inulin in Rat Liver

We tested the hypothesis that the blood to bile transport of hydrophilic inert nonelectrolytes such as inulin is mediated in part by a transcellular pathway involving endosomelike vesicles (transcytosis). Forty minutes after intravenous injection of [3H]methoxyinulin into renal pedicle ligated rats, 0.8% of the radioactivity was recovered in liver homogenate and 85% +/- 3.6% of this radioactivity was associated with membrane bound vesicles. Subcellular fractionation studies and electron microscopy confirmed this association. If rats were treated with taurochenodeoxycholic acid, 5 mumol/100 g body wt, the hepatocellular uptake of [3H]methoxyinulin increased approximately twofold and [3H]methoxyinulin was again recovered in small subcellular vesicles. Furthermore, taurochenodeoxycholic acid also stimulated the biliary excretion of [3H]methoxyinulin, which peaked in bile at 20 min. Taurochenodeoxycholic acid had similar effects on the biliary excretion of horseradish peroxidase, a protein known to be transported from blood to bile by membrane vesicles. Thus under the conditions of these experiments, the dihydroxy bile acid taurochenodeoxycholic acid can stimulate the rate of vesicle-dependent transcellular transport into bile. If inulin clearance represents a maximal estimate of this process, only 6%-8% of total bile production in the rat under basal conditions would be mediated by vesicle-mediated transcytosis.

Hepatic transport of fluorescent molecules: in vivo studies using intravital TV microscopy.

Experiments were undertaken to evaluate the role of intravital epifluorescent TV microscopy in the study of the hepatic transport of sodium fluorescein and fluorescently labeled sodium glycocholate in rats and hamsters. It was found that the apparent sinusoid to canaliculus transport time for fluorescently labeled sodium glycocholate was only half of that for sodium fluorescein, 0.50 and 0.92 sec, respectively. The sinusoid to bile transport time was 35 sec for fluorescently labeled sodium glycocholate and 90 sec for sodium fluorescein. There were also marked differences in zonal clearance of these two substances. Sodium fluorescein was removed from Zone 1 much faster than from Zone 3, while fluorescently labeled sodium glycocholate was cleared at the same rate by hepatocytes in all three acinar zones. This study provides direct evidence that there are zonal differences in hepatic transport rates for certain compounds. It also demonstrates that epifluorescent TV microscopy has the potential to provide quantitative data on the transport rates of bile acids and other molecules into, through and out of the liver.

Hepatic transport of bile salt and bile composition following total parenteral nutrition with and without lipid emulsion in the rat

The effect of total parenteral nutrition (TPN) on bile flow and composition and on hepatic bile acid transport maximum (Tm) and bile salt-independent bile flow (BSIF) was studied in the rat following seven days TPN containing 33% calories from Intralipid (IL) or Liposyn (LP) or 0% calories from lipid. All TPN regimes markedly reduced bile flow. In no case did TPN cause an increase in bile cholesterol concentration or saturation relative to bile acid and phospholipid. Bile acid Tm was reduced in rats receiving either 0% lipid or 33% IL; BSIF was reduced only in the 0% lipid group. Rats receiving 33% LP had a higher bile flow than the other TPN regimes while bile acid Tm and BSIF were similar to controls. It is proposed that in established TPN, bile flow is reduced largely as a result of decreased hepatic bile acid excretion. In the rat, TPN has no deleterious effect on the molar concentration of cholesterol, phospholipid or bile acid in bile secreted by the hepatocyte. The significant differences between the effect of the two lipid emulsions on hepatobiliary function require further study.

Selective transport of serum-derived IgA into mucosal secretions.

The relative contribution of serum-derived and locally produced IgA has been estimated in sheep mammary secretion at various stages of lactation by comparing the transport of radiolabeled IgA and IgG2 from serum to secretions. During early and mid-lactation, but not during involution, serum IgA was selectively transported to mammary secretion on a large scale; in comparison, there was no transport of serum IgA into intestinal secretion. Estimates of local production indicated that the bulk of the IgA in mammary involution secretion and intestinal secretion was locally produced, whereas there was no evidence for local production of IgA in early or mid-lactation secretion. Our studies reveal an inverse relationship between the extent of local production of IgA by plasma cells underlying secretory epithelia and the selective transport of IgA from serum. This finding suggests that selective transport of serum IgA occurs at a number of mucosal sites, but is dependent on secretory component availability, because where local production is predominant, there are fewer secretory component molecules available for serum IgA transport. For this reason, bile transport of IgA does not represent a unique mechanism for the removal of IgA from serum.

Oxygen consumption by rat liver: effects of taurocholate and sulfobromophthalein transport, glucagon, and cation substitution.

The proportion of total hepatic energy utilized for bile formation and transport of taurocholate (TC) and conjugated sulfobromophthalein (cBSP) has not been defined previously. To study this question we have measured changes in oxygen consumption by the isolated perfused rat liver and freshly isolated hepatocytes occurring in response to TC and cBSP administration, cation substitution, and glucagon infusion. The basal rates of bile formation and oxygen consumption varied considerably among different livers, and there was little or no relationship between these two variables. Administration of either TC or cBSP to the perfused liver elicited a marked choleresis but failed to alter steady-state oxygen consumption even at maximal rates of TC or cBSP transport. Similarly, incubation of hepatocytes with TC or cBSP did not alter oxygen consumption. In contrast, inhibition of Na-K-ATPase by removal of sodium and/or potassium from the medium reduced oxygen consumption by perfused rat liver and isolated hepatocytes by 27-37%, and glucagon administration increased oxygen consumption in both systems by 31-40%. These findings indicate that the oxygen requirement for bile formation and even maximal rates of TC and cBSP transport is small compared with that for the metabolic changes induced by glucagon or for hepatic Na-K-ATPase activity. This is in contrast to other epithelial tissues, such as kidney and rectal gland, in which oxygen utilization for transepithelial solute and water transport constitutes a large fraction of both total and Na-K-ATPase-dependent oxygen consumption.

Plasma Clearance of 99mTc-N/2,4-Dimethyl-Acetanilido/Iminodiacetate Complex as a Measure of Parenchymal Liver Damage

Fifty-two patients were studied with various diseases affecting liver parenchyma. Any disorders of bile transport were excluded on the basis of dynamic liver scintigraphy using intravenously injected N/2,4-dimethyl acetanilido/iminodiacetate 99mTc complex (HEPIDA). The activity concentration of 99mTc-HEPIDA in plasma was measured from 5 through 60 min post injection. Clearance of the substance (ClB) was calculated from blood plasma disappearance curves and compared with results of 13 laboratory tests used conventionally for assessment of damage of the liver and its functional capacity; age and body weight was also included in the analysis. Statistical relations were studied using linear regression analysis of two variables, multiple regression analysis as well as multidimensional analysis of variance. It was demonstrated that 99mTc-HEPIDA clearance is a simple, accurate and repeatable measure of liver parenchyma damage. In males, values of ClB above 245 ml. min-1/1.73 m2 exclude hepatic damage with high probability; values below 195 ml.min-1/1.73 m2 indicate evident impairment of liver parenchyma function.

Effects of intra-arterial prostaglandin E2 on gallbladder fluid transport, motility, and hepatic bile in the cat.

The effects of intra-arterial infusion of prostaglandin E2 on gallbladder concentrating function, motility, and hepatic bile flow were studied simultaneously in the anesthetized cat by means of a perfusion technique. Prostaglandin E2 reversibly inhibited gallbladder net fluid absorption and in some cases reversed the direction of transport to a net fluid secretion. A contraction of the gallbladder and an increased flow of hepatic bile were seen during prostaglandin infusion. The results are discussed in relation to the role of prostaglandins in the pathophysiology of cholecystitis.

Fate of lentinan (antitumor polysaccharide) II : - fast of methyl lentinan in rats (author's transl)

3H-labeled lentinan was prepared by methylation with 3H-dimethyl-sulfate. Blood level, distribution and excretion were studied in rats. After intravenous injection of [methyl-3H] -methyl lentinan, radioactivity rapidly disappeared from blood, lung and kidney, distributed mainly in liver, spleen and mesenteric lymph nodes. There was urinary excretion, but expiratory excretion was a small proportion. In the case of multi-injection of [methyl-3H] -methyl lentinan distribution of radioactivity was similar to a single injection, but retention of 3H was less than a single injection. Bile excretion and transport to fetuses and milk were in mere trace amounts. No substantial difference was found between two types of the 3H-labeled lentinan in either the distribution or excretion.

Enzyme activities as electron microscopic markers of bile and bile thrombi in the study of cholestasis.

An electron microscopical study of several phosphatases in liver tissue was made in different forms of cholestasis. The material included a biopsy from a case of giant cell hepatitis, dog liver after experimental common bile duct ligation, and rat liver under the same experimental conditions. A positive reaction of several phosphatases was noted in the sites of intra and extracellular accumulation of bile constituents. It is suggested that the activity of phosphatases, especially the alkaline phosphatase activity, can be useful as an electron microscopic marker of intracytoplasmic and intercellular bile constituents in the study of bile transport and bile regurgitation. The supposition is made that the intracytoplasmic bilirubin carrier protein can be of enzymatic character.

Bidirectional transport of taurocholate by the proximal tubule of the dog.

ARTICLESBidirectional transport of taurocholate by the proximal tubule of the dogGR Zins, and IM WeinerGR Zins, and IM WeinerPublished Online:01 Oct 1968https://doi.org/10.1152/ajplegacy.1968.215.4.840MoreSectionsPDF (1 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByAre Bile Acids Involved in the Renal Dysfunction of Obstructive Jaundice? An Experimental Study in Bile Duct Ligated Rats7 July 2009 | Renal Failure, Vol. 26, No. 5Ontogenic expression of the Na+-independent organic anion transporting polypeptide (oatp) in rat liver and kidneyJournal of Hepatology, Vol. 25, No. 6Renal Excretion and Tubular Transport of Organic Anions and Cations1 January 2011Urinary Bile AcidsAltered metabolism of bile alcohol and bile acid in complete extrahepatic cholestasis: qualitative and quantitative aspectsJournal of Lipid Research, Vol. 28, No. 9Urographic Contrast Media and Methods of Investigative UroradiologyEffect of cephapirin on tubular reabsorption of amino acids, uric acid and beta 2-microglobulin in man.26 July 2012 | British Journal of Clinical Pharmacology, Vol. 15, No. 3Renal tubular handling of drugsThe American Journal of Medicine, Vol. 62, No. 4Proximal Tubular Transport and Renal Metabolism of Organic Cations and CatecholThe Renal Excretion of DrugsIn Vitro Uptake of Bile Acids by Choroid Plexus, Kidney Cortex and Anterior Uvea. I. The Iodipamide-sensitive Transport Systems in the RabbitActa Physiologica Scandinavica, Vol. 93, No. 2Bile Salt Transport SystemsTransport of DrugsExcretion of Drugs by the Kidney More from this issue > Volume 215Issue 4October 1968Pages 840-845 Copyright & PermissionsCopyright © 1968 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1968.215.4.840PubMed5676386History Published online 1 October 1968 Published in print 1 October 1968 Metrics

The structure of choleic acids.

This article reviews evidence for the inclusion compound structure of the choleic acids and their possible significance with respect to the transport of bile.

Progress in Liver Diseases

Since the appearance of volume 1 ofProgress in Liver Diseasessome four years ago, great advances have been made in the field of experimental and applied hepatology. Volume 2 reflects these forward steps. Advances have been made in the understanding of the mechanisms of bile metabolism and transport and also of bile secretion. A superb, although encyclopedic, presentation of the ultrastructure of the liver and detailed description of viral hepatitis is given by J. W. Steiner et al. Geographic and genetic pathology are also included in this volume. For the first time, a detailed presentation is given of the ultrastructural and functional relationships in hepatic drug detoxification. An excellent and thorough presentation by Kent, on iron storage diseases and the liver, is also included. The editors should be congratulated on accepting for publication certain controversial topics such as fibrosis, primary biliary cirrhosis, and cholestasis. This volume is well balanced.

Human hepatocellular pigments and lysosomes

The fine structure of human hepatocellular granules containing lipofuscin, the pigment of chronic idiopathic jaundice (Dubin-Johnson), or bile pigment (obstructive jaundice) are described. Because of their fine structure and acid phosphatase activities all these granules are considered to be altered lysosomes. Iron-containing granules in human liver cells are also considered to be derived from lysosomes. This is based on their pericanalicular arrangement, size, and acid phosphatase activity. Parallel studies in spleen macrophages of the rat are referred to. Our findings provide evidence for the suggestion that the pericanalicular dense bodies are the lysosomes of the hepatic cell. Of special interest to pathologists are: (a) the unique structure of bile pigment deposits found within the cells, bile canaliculi, and sinusoids of the obstructed liver; (b) the differences in fine structure and distribution of acid phosphatase activity between the pigment of chronic idiopathic jaundice (Dubin-Johnson) and hepatocellular lipofuscin; (c) the fine structure of lipofuscin granules; and (d) the general roles suggested for lysosomes in the physiology and pathology of cells, including a role in the intracellular transport of bile.

Newer concepts concerning the common bile duct.

THE COMMON bile duct is a conduit serving to transport bile from the liver to the duodenum. This pipeline includes a surge chamber (represented by the gall bladder) permitting both storage and availability. The duct also has a nozzle at its termination, which increases the flow of bile to jetstream velocity. These concepts conform to hydraulic principles. The common bile duct has a constantly curving course. Its termination at the papilla of Vater is like a funnel in that the diameter of the lumen decreases rapidly. The external appearance of the terminal (transduodenal) segment of the common bile duct is that of an expanded bulb. This enlargement occurs where the pancreatic duct appears to join the termination of the common bile duct. This bulbous character, for many years, led to a belief that a space was formed by the confluence of the pancreatic and common bile ducts. When the enlarged