scholarly journals Comparative studies on bile flow and biliary lipid excretion after bile-acid loading in normal and partially hepatectomized rats

1995 ◽  
Vol 305 (2) ◽  
pp. 367-371 ◽  
Author(s):  
M Hoshino ◽  
A Hirano ◽  
T Hayakawa ◽  
Y Kamiya ◽  
T Ohiwa ◽  
...  
Keyword(s):  
Bile Acid ◽  
Rat Liver ◽  
Bile Flow ◽  
Acid Output ◽  
Bile Secretion ◽  
Biliary Lipid ◽  
Isolated Perfusion ◽  
Acid Loading ◽  
Second Peak

This study was performed to investigate sequential changes in bile secretion and biliary lipids after taurocholic acid (TCA) loading of regenerating rat liver. TCA was administered intravenously at stepwise-increasing doses to groups of non-operated control and partially hepatectomized rats, 24, 72 and 168 h after surgery. Bile flow, bile-acid output (BAO) and phospholipid output (PLO) (expressed per gram of liver) in partially hepatectomized rats increased more than in the controls. Using an isolated perfusion rat-liver system, TCA infusion was also carried out on groups of non-operated control and hepatectomized rats 72 h after operation. Again bile flow, BAO and PLO (expressed per gram of liver) were significantly higher in the partial hepatectomy case, mirroring the results obtained in vivo. When horseradish peroxidase (HRP) was pulse-loaded in isolated perfusion preparations, the second peak of biliary HRP secretion in hepatectomized rats was significantly higher than in controls. We conclude that increased bile-acid flow in partially hepatectomized rats is dependent upon acceleration of vesicular transport accompanying or following proliferation in regenerating livers.

Bile secretion in rats with indomethacin-induced intestinal inflammation

1996 ◽  
Vol 270 (5) ◽  
pp. G804-G812 ◽  
Author(s):  
T. Yamada ◽  
M. Hoshino ◽  
T. Hayakawa ◽  
Y. Kamiya ◽  
H. Ohhara ◽  
...  
Keyword(s):  
Bile Acid ◽  
Bile Salt ◽  
Bile Flow ◽  
Intestinal Inflammation ◽  
Acid Output ◽  
Bile Secretion ◽  
Pool Size ◽  
Secretory Function ◽  
Indomethacin Treatment

The objective of this study was to characterize the bile secretion, including the composition of biliary bile acids, bile salt pool size, and transcytotic vesicle transport, in a rat model of subacute intestinal inflammation induced by indomethacin. Indomethacin treatment significantly decreased bile acid-independent bile flow and biliary secretion of bile acid and cholesterol, while increasing biliary phospholipid output in vivo. Although indomethacin treatment did not change the bile salt pool size in vivo, alpha- and beta-muricholic acids were significantly deceased and hyodeoxycholic and deoxycholic acids were increased in bile. Bile flow and the transport maximum of taurocholate did not decrease, and biliary horseradish peroxidase output was significantly enhanced in isolated perfused livers from indomethacin-treated rats. Endotoxin in the portal blood was significantly increased in rats treated with indomethacin. Clindamycin slightly reduced intestinal inflammation but significantly prevented decreases in bile flow, bile acid output, and transport maximum of taurocholate. We conclude that, although biliary secretory function was apparently decreased in vivo, that of hepatocyte function was maintained in this model.

Endothelin-1 stimulates bile acid secretion and vesicular transport in the isolated perfused rat liver

1994 ◽  
Vol 266 (2) ◽  
pp. G324-G329 ◽  
Author(s):  
A. Tanaka ◽  
K. Katagiri ◽  
M. Hoshino ◽  
T. Hayakawa ◽  
K. Tsukada ◽  
...  
Keyword(s):  
Bile Acid ◽  
Rat Liver ◽  
Bile Flow ◽  
Low Dose ◽  
Portal Pressure ◽  
Vesicular Transport ◽  
Bile Secretion ◽  
Isolated Perfused Rat Liver ◽  
High Dose ◽  
Perfused Rat Liver

The effects of endothelin (ET) on portal pressure and bile secretion were examined using isolated perfused rat liver and rat hepatocyte preparations. ET-1 raised portal pressure dose dependently; administration at a high dose (10(-9) mol) induced a > 200% increase along with reduced bile flow and decreased secretion of bile acid and phospholipids. However, a low dose (10(-10) mol) of ET-1 brought about a < 100% portal pressure rise, enhanced both bile flow and excretion of bile acid and phospholipids, and significantly increased transfer of preadministered horseradish peroxidase (HRP) into bile. In addition, values for Ca2+ concentrations, examined by indo 1 fluorescence, were elevated in isolated hepatocytes after administration of ET-1. Papaverine suppressed the low-dose ET-1 stimulation effects on both portal pressure and bile secretion. Moreover, it also reduced the HRP excretion and suppressed intracellular Ca2+ release. This study demonstrated that ET-1 stimulates vesicular transport, probably via promotion of intracellular Ca2+ release, and, as a result, increases bile acid-dependent bile flow.

Pre-replicative phase-related changes in bile acid-induced choleresis in the regenerating rat liver

1990 ◽  
Vol 78 (1) ◽  
pp. 55-62 ◽  
Author(s):  
J. J. Garcia-Marin ◽  
P. Regueiro ◽  
J. C. Perez-Antona ◽  
G. R. Villanueva ◽  
F. Perez-Barriocanal
Keyword(s):  
Bile Acid ◽  
Ursodeoxycholic Acid ◽  
Cholic Acid ◽  
Rat Liver ◽  
Bile Flow ◽  
Acid Output ◽  
Liver Weight ◽  
Bicarbonate Secretion ◽  
Regenerating Rat Liver ◽  
Bicarbonate Output

1. During the pre-replicative phase of the regenerating rat liver some interesting changes occur, which might selectively modify some mechanisms involved in bile formation, such as those responsible for the hypercholeretic effect of ursodeoxycholic acid. The aim of the present work was to gain information on this point. 2. Anaesthetized male Wistar rats (∼ 250 g) were used. The animals underwent two-thirds hepatectomy 1, 6 or 12 h before collection of bile samples was begun. Very early after hepatectomy (1 h) spontaneous bile flow and bile acid output were increased. Both returned to values not significantly different from those of the controls at 6 h. Bile flow increased again at the end of the pre-replicative phase. Taurocholate infusion (200 nmol min−1 g−1 calculated liver weight) induced increases in bile flow and bile acid output that were similar in both the control and hepatectomized rats, regardless of the time of the pre-replicative phase considered. 3. Cholic acid and ursodeoxycholic acid were infused (300 nmol min−1 g−1 calculated liver weight) into control and partially hepatectomized rats (at the mid-point of the pre-replicative phase, i.e. 6 h after surgical liver resection). Cholic acid-induced bile flow, bile acid and bicarbonate output expressed per g of remaining liver were similar in control and in hepatectomized rats. By contrast, ursodeoxycholic acid-induced choleresis was profoundly altered during the pre-replicative phase. As expressed per g of remaining liver, bile flow was markedly reduced (− 17%, P < 0.05), in spite of total bile acid output being greatly increased (+ 148%, P < 0.001). The reduced choleretic effect of ursodeoxycholic acid may be due to a lowered stimulation of bicarbonate secretion (− 41%, P < 0.01). 4. Factors known to reduce ursodeoxycholic acid-induced bicarbonate secretion into bile, such as decreased plasma bicarbonate concentrations and lowered total hepatic carbonic anhydrase activity, cannot account for the loss of the ability of ursodeoxycholic acid to stimulate bicarbonate secretion during the pre-replicative phase. However, the bile acid conjugation patterns were dramatically altered early after hepatectomy (6 h). In bile from the control animals the major ursodeoxycholic acid conjugation was with glycine, whereas in hepatectomized rats it was with taurine. 5. In summary, our results indicate that during the prereplicative phase of the regenerating rat liver, a loss occurs in the hypercholeretic effect of bile acids such as ursodeoxycholic acid. However, the choleretic effect of non-hypercholeretic bile acids such as cholic acid and taurocholic acid was not altered. Moreover, the existence of a relationship between the decrease in bile flow and bicarbonate output and the marked increase in the secretion of low-pKa conjugated bile acid derivatives is suggested.

Influence of bile acid structure on bile flow and biliary lipid secretion in the hamster

1984 ◽  
Vol 247 (6) ◽  
pp. G736-G748 ◽  
Author(s):  
D. Gurantz ◽  
A. F. Hofmann
Keyword(s):  
Bile Acid ◽  
Bile Acids ◽  
Bile Flow ◽  
Enterohepatic Circulation ◽  
Acid Output ◽  
Chain Structure ◽  
Side Chain ◽  
Biliary Lipid ◽  
Lipid Secretion ◽  
Acid Structure

A comprehensive study of the influence of bile acid structure on bile flow and biliary lipid secretion was carried out by infusing pure bile acids at a physiological rate into the proximal small intestine of a bile fistula hamster. Twelve individual bile acids, cholate (C), ursocholate (UC), chenodeoxycholate (CDC), and ursodeoxycholate (UDC) as their glycine (G), taurine (T), or unconjugated form, were studied so that influence of the hydroxy substituents as well as side-chain structure could be defined. The pattern of bile acid output was dependent on bile acid structure and reflected the site and rate of intestinal absorption. Conjugated bile acid output was delayed because of late ileal absorption, and TUC was poorly absorbed. Unconjugated trihydroxy bile acids, C and UC, also exhibited a delay in absorption, while CDC and UDC were absorbed immediately and achieved the highest bile acid output. Unconjugated bile acids were conjugated initially mostly with taurine and then mostly with glycine. The effect of glycine conjugates of each bile acid on bile flow and biliary lipid secretion was similar to that of their corresponding taurine conjugates. All conjugated bile acids induced a similar rate of bile flow (9–15 microliter bile/mumol bile acid), but unconjugated bile acids other than C induced more flow (20–25 microliter bile/mumol bile acid) than their corresponding conjugates. Conjugates of the dihydroxy bile acids induced a greater secretion of phospholipid and cholesterol than cholyl conjugates, whereas conjugates of UC were unique in inducing extremely low phospholipid and cholesterol secretion. For an increase of 1 mumol X min-1 X kg-1 in bile acid output, the increase in phospholipid secretion was 0.072 mumol X min X kg for GCDC and TCDC; 0.051 mumol X min-1 X kg-1 for GUDC and TUDC; and 0.030 mumol X min-1 X kg-1 for GC and TC. Increase in cholesterol output per mumol X min-1 X kg-1 of bile acid output was 0.013 mumol X min-1 X kg-1 for GCDC and TCDC, 0.011 mumol X min-1 X kg-1 for GUDC and TUDC, and 0.005 mumol X min-1 X kg-1 for GC and TC. In general, unconjugated bile acids induced more phospholipid and cholesterol than their corresponding conjugates; however, the rank-order effect of the steroid nucleus substituents was similar to that observed for the respective conjugates. These results indicate that both nuclear and side-chain structure influence the enterohepatic circulation and biliary secretory properties of bile acids.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Impaired Bile Secretion Promotes Chronic Liver Injury in Sickle Cell Disease

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3536-3536
Author(s):  
Tirthadipa Pradhan ◽  
Prithu Sundd ◽  
Mark T Gladwin ◽  
Satdarshan Pal Monga ◽  
Gregory J Kato
Keyword(s):  
Bile Acid ◽  
Sickle Cell ◽  
Bile Flow ◽  
Research Funding ◽  
Acid Synthesis ◽  
Bile Acid Synthesis ◽  
Bile Secretion ◽  
Cell Disease ◽  
Flow Through

Hepatic crisis is an emergent complication affecting sickle cell disease (SCD) patients, however, the molecular mechanism of sickle cell hepatobiliary crisis remains poorly understood. We examined the liver pathophysiology of SCD using a humanized mouse model (townes SCD mice; homozygous for Hbatm1(HBA)Tow, homozygous for Hbbtm2(HBG1,HBB*)Tow). These mice have the major features (irreversibly sickled red cells, splenomegaly, anemia, multiorgan pathology) found in humans with SCD and, as such, represent a useful in vivo system to study hepatobiliary changes in SCD disease. SCD mice manifested progressive hepatomegaly, liver injury and hyperbilirubinemia. RNA-sequence analysis of total RNA from SCD mouse liver compared to control (AS) identified dysregulation of genes encoding proteins responsible for fibrosis, bile acid synthesis, bile transport and cholesterol metabolism. Immunohistochemical analysis confirmed inflammation, fibrosis and increased ductular reaction in SCD mice. To mechanistically address the cholestatic phenotype in SCD mice, we used our recently developed multi-photon-excitation (MPE) enabled in vivo real-time fluorescence microscopy of intact liver in live mice. We used Texas-Red (TXR) dextran to visualize the blood flow through liver sinusoids and carboxyfluorescein (used as a surrogate of bile flow) to visualize bile flow through biliary canaliculi. Real time imaging show that sinusoidal ischemia occurs in the liver of transgenic-humanized SCD mice under basal condition. Intravital imaging also revealed impaired bile secretion into the bile canaliculi, which was associated with loss of apical bile acid transporters and bile acid biosynthetic enzymes, hepatic bile accumulation, and activation of Farnesoid X receptor (FXR) and small heterodimer partner (Shp) in the liver of SCD mice. These findings are the first to identify that impaired bile acid synthesis and misexpression of bile transporters promote intrahepatic bile accumulation and impaired bile secretion, leading to hepatobiliary injury of SCD. Improved understanding of these processes could potentially benefit the development of new therapies to treat sickle cell hepatic crisis. Disclosures Gladwin: Globin Solutions, Inc: Patents & Royalties: Provisional patents for the use of recombinant neuroglobin and heme-based molecules as antidotes for CO poisoning; Bayer Pharmaceuticals: Other: Co-investigator; United Therapeutics: Patents & Royalties: Co-inventor on an NIH government patent for the use of nitrite salts in cardiovascular diseases . Kato:Novartis, Global Blood Therapeutics: Consultancy, Research Funding; Bayer: Research Funding.

scholarly journals Short- and long-term effects of biliary drainage on hepatic cholesterol metabolism in the rat

1990 ◽  
Vol 269 (3) ◽  
pp. 781-788 ◽  
Author(s):  
M J Smit ◽  
A M Temmerman ◽  
R Havinga ◽  
F Kuipers ◽  
R J Vonk
Keyword(s):  
Bile Acid ◽  
Bile Flow ◽  
Cholesterol Metabolism ◽  
Acid Output ◽  
Biliary Secretion ◽  
Surgical Trauma ◽  
Hepatic Cholesterol ◽  
Long Term Effects ◽  
Short And Long Term

The present study concerns short- and long-term effects of interruption of the enterohepatic circulation (EHC) on hepatic cholesterol metabolism and biliary secretion in rats. For this purpose, we employed a technique that allows reversible interruption of the EHC, during normal feeding conditions, and excludes effects of anaesthesia and surgical trauma. [3H]Cholesteryl oleate-labelled human low-density lipoprotein (LDL) was injected intravenously in rats with (1) chronically (8 days) interrupted EHC, (2) interrupted EHC at the time of LDL injection and (3) intact EHC. During the first 3 h after interruption of the EHC, bile flow decreased to 50% and biliary bile acid, phospholipid and cholesterol secretion to 5%, 11% and 19% of their initial values respectively. After 8 days of bile diversion, biliary cholesterol output and bile flow were at that same level, but bile acid output was increased 2-3-fold and phospholipid output was about 2 times lower. The total amount of cholesterol in the liver decreased after interruption of the EHC, which was mainly due to a decrease in the amount of cholesteryl ester. Plasma disappearance of LDL was not affected by interruption of the EHC. Biliary secretion of LDL-derived radioactivity occurred 2-4 times faster in chronically interrupted rats as compared with the excretion immediately after interruption of the EHC. Radioactivity was mainly in the form of bile acids under both conditions. This study demonstrates the very rapid changes that occur in cholesterol metabolism and biliary lipid composition after interruption of the EHC. These changes must be taken into account in studies concerning hepatic metabolism of lipoprotein cholesterol and subsequent secretion into bile.

In Vitro Metabolism of E2, G2: Novel Bile Acid-Coupling Camptothecin Analogues, in Rat Liver Microsomes

2021 ◽  
Vol 16 ◽  
Author(s):  
Xiangli Zhang ◽  
Qin Shen ◽  
Yi Wang ◽  
Leilei Zhou ◽  
Qi Weng ◽  
...  
Keyword(s):  
Bile Acid ◽  
Phase I ◽  
Rat Liver ◽  
Deoxycholic Acid ◽  
Liver Microsomes ◽  
Intrinsic Clearance ◽  
Rat Liver Microsomes ◽  
Camptothecin Analogues

Background: E2 (Camptothecin - 20 (S) - O- glycine - deoxycholic acid), and G2 (Camptothecin - 20 (S) - O - acetate - deoxycholic acid) are two novel bile acid-derived camptothecin analogues by introducing deoxycholic acid in 20-position of CPT(camptothecin) with greater anticancer activity and lower systematic toxicity in vivo. Objective: We aimed to investigate the metabolism of E2 and G2 by Rat Liver Microsomes (RLM). Methods: Phase Ⅰ and Phase Ⅱ metabolism of E2 and G2 in rat liver microsomes were performed respectively, and the mixed incubation of phase I and phase Ⅱ metabolism of E2 and G2 was also processed. Metabolites were identified by liquid chromatographic/mass spectrometry. Results: The results showed that phase I metabolism was the major biotransformation route for both E2 and G2. The isoenzyme involved in their metabolism had some difference. The intrinsic clearance of G2 was 174.7mL/min. mg protein, more than three times of that of E2 (51.3 mL/min . mg protein), indicating a greater metabolism stability of E2. 10 metabolites of E2 and 14 metabolites of G2 were detected, including phase I metabolites (mainly via hydroxylations and hydrolysis) and their further glucuronidation products. Conclusion: These findings suggested that E2 and G2 have similar biotransformation pathways except some difference in the hydrolysis ability of the ester bond and amino bond from the parent compounds, which may result in the diversity of their metabolism stability and responsible CYPs(Cytochrome P450 proteins).

Differing effects of norcholate and cholate on bile flow and biliary lipid secretion in the rat

1984 ◽  
Vol 246 (1) ◽  
pp. G67-G71
Author(s):  
E. R. O'Maille ◽  
S. V. Kozmary ◽  
A. F. Hofmann ◽  
D. Gurantz
Keyword(s):  
Bile Acid ◽  
Acid Secretion ◽  
Bile Acids ◽  
Bile Flow ◽  
Critical Micellar Concentration ◽  
Biliary Lipid ◽  
Lipid Secretion ◽  
Unit Increase ◽  
Cholesterol Secretion ◽  
Bile Acid Secretion

The effects of norcholate (a C23 bile acid that differs from cholate in having a side chain containing four rather than five carbon atoms) on bile flow and biliary lipid secretion were compared with those of cholate, using the anesthetized rat with a bile fistula. Norcholate and cholate were infused intravenously over the range of 0.6-6.0 mumol X min-1 X kg-1. Both bile acids were quantitatively secreted into bile; norcholate was secreted predominantly in unconjugated form in contrast to cholate, which was secreted predominantly as its taurine or glycine conjugates. The increase in bile flow per unit increase in bile acid secretion induced by norcholate infusion [17 +/- 3.2 (SD) microliters/mumol, n = 8] was much greater than that induced by cholate infusion (8.6 +/- 0.9 microliters/mumol, n = 9) (P less than 0.001). Both bile acids induced phospholipid and cholesterol secretion. For an increase in bile acid secretion (above control values) of 1 mumol X min-1 X kg-1, the increases in phospholipid secretion [0.052 +/- 0.024 (SD) mumol X min-1 X kg-1, n = 9] and cholesterol secretion (0.0071 +/- 0.0033 mumol X min-1 X kg-1, n = 9) induced by norcholate infusion were much less than those induced by cholate infusion (0.197 +/- 0.05 mumol X min-1 X kg-1, n = 9, and 0.024 +/- 0.011 mumol X min-1 X kg-1, n = 9, respectively; P less than 0.001 for both phospholipid and cholesterol). The strikingly different effects of norcholate on bile flow and biliary lipid secretion were attributed mainly to its possessing a considerably higher critical micellar concentration than cholate.

Nifedipine modulation of biliary GSH and GSSG/ conjugate efflux in normal and regenerating rat liver

2001 ◽  
Vol 281 (1) ◽  
pp. G85-G94 ◽  
Author(s):  
Bo Yang ◽  
Ceredwyn E. Hill
Keyword(s):  
Bile Acid ◽  
Sodium Nitroprusside ◽  
Rat Liver ◽  
Driving Force ◽  
Bile Flow ◽  
Organic Anion ◽  
High Capacity ◽  
Perfused Rat Liver ◽  
High Affinity ◽  
Glutathione Conjugate Transport

Canalicular glutathione secretion provides the major driving force for bile acid-independent bile flow (BAIF), although the pathways involved are not established. The hypothesis that GSH efflux proceeds by a route functionally distinct from the high-affinity, low-capacity, mrp2-mediated pathway was tested by using perfused rat liver and three choleretic compounds that modify biliary secretion of GSH (the dihydropyridine nifedipine and organic anion probenecid) or GSSG [sodium nitroprusside (SNP)]. Whereas nifedipine (30 μM) stimulated GSH secretion and blocked SNP-stimulated GSSG efflux and choleresis, SNP (1 mM) was ineffective against nifedipine-stimulated GSH efflux or BAIF, suggesting that most GSSG exits through a GSH-inhibitable path independent of high-affinity GSSG/glutathione conjugate transport. Three observations support this proposal. SNP, but not nifedipine, significantly inhibited bromosulfophthalein (BSP, 1 μM) excretion. Probenecid (1 mM) blocked resting or nifedipine-stimulated GSH secretion but only weakly inhibited BSP excretion. Glutathione, but not BSP, efflux capacity was reduced following partial hepatectomy. We suggest GSH efflux is mediated by a high-capacity organic anion pathway capable of GSSG transport when its high-affinity route is saturated.

Sign in / Sign up

Export Citation Format

Share Document