scholarly journals Ultrastructural Characteristics of Rat Hepatic Oval Cells and Their Intercellular Contacts in the Model of Biliary Fibrosis: New Insights into Experimental Liver Fibrogenesis

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Joanna Maria Lotowska ◽  
Maria Elzbieta Sobaniec-Lotowska ◽  
Dariusz Marek Lebensztejn ◽  
Urszula Daniluk ◽  
Piotr Sobaniec ◽  
...  
Keyword(s):  
Bile Duct ◽  
Cell Contact ◽  
Oval Cells ◽  
Cellular Interactions ◽  
Nonparenchymal Cells ◽  
Transmission Electron ◽  
Duct Ligation ◽  
Liver Fibrogenesis ◽  
Direct Cell ◽  
Hepatic Nonparenchymal Cells

Purpose. Recently, it has been emphasized that hepatic progenitor/oval cells (HPCs) are significantly involved in liver fibrogenesis. We evaluated the multipotential population of HPCs by transmission electron microscope (TEM), including relations with adherent hepatic nonparenchymal cells (NPCs) in rats with biliary fibrosis induced by bile duct ligation (BDL). Methods. The study used 6-week-old Wistar Crl: WI(Han) rats after BDL for 1, 6, and 8 weeks. Results. Current ultrastructural analysis showed considerable proliferation of HPCs in experimental intensive biliary fibrosis. HPCs formed proliferating bile ductules and were scattered in periportal connective tissue. We distinguished 4 main types of HPCs: 0, I, II (bile duct-like cells; most common), and III (hepatocyte-like cells). We observed, very seldom presented in literature, cellular interactions between HPCs and adjacent NPCs, especially commonly found transitional hepatic stellate cells (T-HSCs) and Kupffer cells/macrophages. We showed the phenomenon of penetration of the basement membrane of proliferating bile ductules by cytoplasmic processes sent by T-HSCs and the formation of direct cell-cell contact with ductular epithelial cells related to HPCs. Conclusions. HPC proliferation induced by BDL evidently promotes portal fibrogenesis. Better understanding of the complex cellular interactions between HPCs and adjacent NPCs, especially T-HSCs, may help develop antifibrotic therapies in the future.

Typing of hepatic nonparenchymal cells using fibulin-2 and cytoglobin/STAP as liver fibrogenesis-related markers

2004 ◽  
Vol 122 (1) ◽  
Author(s):  
Yuko Tateaki ◽  
Tomohiro Ogawa ◽  
Norifumi Kawada ◽  
Toshihiko Kohashi ◽  
Koji Arihiro ◽  
...  
Keyword(s):  
Nonparenchymal Cells ◽  
Liver Fibrogenesis ◽  
Hepatic Nonparenchymal Cells

Regulation of inducible nitric oxide synthase and nitric oxide during hepatic injury and fibrogenesis

1997 ◽  
Vol 273 (1) ◽  
pp. G124-G130 ◽  
Author(s):  
D. C. Rockey ◽  
J. J. Chung
Keyword(s):  
Nitric Oxide ◽  
Carbon Tetrachloride ◽  
Bile Duct ◽  
Kupffer Cells ◽  
Hepatic Injury ◽  
Bile Duct Ligation ◽  
Inos Mrna ◽  
No Production ◽  
Nonparenchymal Cells ◽  
Duct Ligation

Nitric oxide (NO) production via inducible NO synthase (iNOS) is prominent in the liver after stimulation with cytokines and/or lipopolysaccharide. The aim of this study was to investigate the production of NO via iNOS in specific liver cell populations during toxin-mediated and obstructive hepatic injury and fibrogenesis. After a single dose of carbon tetrachloride, iNOS mRNA and nitrite (a metabolic product of NO) were detected only in Kupffer cells. They were not detectable in any cell type after recurrent administration of carbon tetrachloride, including in animals with far advanced cirrhosis (i.e., portal hypertension and/or ascites). After bile duct ligation, a mechanistically different form of liver injury and fibrogenesis, iNOS mRNA and nitrite were identified in all nonparenchymal cells but not in hepatocytes. Twenty-four hours after bile duct ligation, iNOS mRNA and NO production were greatest in Kupffer cells, but after prolonged bile duct ligation, iNOS was found predominantly in sinusoidal endothelial cells. These data indicate that iNOS expression varies temporally and spatially in the liver after injury and also varies with the type of insult.

Transcytotic vesicular carriers for polymeric IgA receptors accumulate in rat hepatocytes after bile duct ligation

1991 ◽  
Vol 98 (2) ◽  
pp. 205-216 ◽  
Author(s):  
J.M. Larkin ◽  
G.E. Palade
Keyword(s):  
Bile Duct ◽  
Serum Proteins ◽  
Bile Duct Ligation ◽  
Rat Hepatocytes ◽  
Frozen Sections ◽  
Transmission Electron ◽  
Duct Ligation ◽  
Sds Page ◽  
Vesicular Carriers

In rat hepatocytes, transcytotic vesicular carriers transport the mature 120 × 10(3) Mr form of the polymeric IgA receptor (pIgA-R), with or without its ligand, pIgA, from the sinusoidal to the biliary plasmalemma, where the ectodomain of the receptor is cleaved to produce an 80 × 10(3) Mr fragment that is secreted into the bile. Here we show that cholestasis induced by bile duct ligation results in the accumulation of transcytotic carriers, identified by the 120 × 10(3) Mr pIgA-R and pIgA, in the pericanalicular cytoplasm of hepatocytes. To determine the extent of pIgA-R accumulation, hepatic total microsomes (TM) were prepared from control and cholestatic rats. Solubilized TM proteins were separated by SDS-PAGE and receptor forms were detected by immunoblotting and autoradiography. Quantitative densitometry of these autoradiograms showed that after duct ligation the 120 × 10(3) Mr receptor accumulated to a level approximately threefold higher than the control. Concomitantly, immunologically related, novel 124, 90 and 80 × 10(3) Mr proteins (cholestatic antigens) became detectable. Immunoblot analyses of biliary and serum proteins showed that cholestasis resulted in: (1) a marked decrease in the concentrations of the 80 × 10(3) Mr receptor and pIgA in the bile, whereas albumin concentrations remained at control levels; and (2) a marked increase in the concentration of the 80 × 10(3) Mr receptor in the serum. Positive sites for pIgA-R were localized to the pericanalicular cytoplasm of hepatocytes by indirect immunofluorescence on semithin frozen sections in cholestatic hepatocytes. The sites were more numerous and the positive signal stronger than in controls. One day post-ligation, pIgA-positive sites were located to the same pericanalicular cytoplasm of hepatocytes; by three days, however, most pIgA appeared in sinusoidal endothelia and Kupffer cells. To validate the vesicular character of the receptor-positive sites, sham-operated and cholestatic livers were processed for either transmission electron microscopy (TEM) or immunogold localization of receptors on thin frozen sections. TEM verified the accumulation of pericanalicular vesicles in cholestatic hepatocytes. Immunogold tests localized pIgA-R to pleiomorphic, pericanalicular vesicles, which were increased in number, size and concentration of antigenic sites in cholestatic hepatocytes. These findings indicate that bile duct ligation provides a method for manipulating the in vivo transcytotic pathway and for accumulating previously unstudied transcytotic carriers in hepatocytes.

Bid-mediated apoptosis does not contribute to cholestatic liver injury following bile duct ligation

2009 ◽  
Vol 47 (01) ◽  
Author(s):  
P Nalapareddy ◽  
S Schüngel ◽  
MP Manns ◽  
H Jaeschke ◽  
A Vogel
Keyword(s):  
Bile Duct ◽  
Liver Injury ◽  
Bile Duct Ligation ◽  
Duct Ligation ◽  
Cholestatic Liver Injury

HGF/c-Met and IL-6/gp130 cooperatively regulate liver homeostasis and antibacterial signalling after bile-duct-ligation

2010 ◽  
Vol 48 (01) ◽  
Author(s):  
A Giebeler ◽  
S Erschfeld ◽  
C Birchmeier ◽  
C Trautwein ◽  
KL Streetz
Keyword(s):  
Bile Duct ◽  
Bile Duct Ligation ◽  
Duct Ligation

Impaired Fibrinolysis in Obstructive Jaundice - Evidence from Clinical and Experimental Studies

1988 ◽  
Vol 60 (01) ◽  
pp. 025-029 ◽  
Author(s):  
M Colucci ◽  
D F Altomare ◽  
G Chetta ◽  
R Triggiani ◽  
L G Cavallo ◽  
...  
Keyword(s):  
Renal Failure ◽  
Bile Duct ◽  
Obstructive Jaundice ◽  
Plasminogen Activator ◽  
Fibrinolytic Activity ◽  
Experimental Studies ◽  
Plasminogen Activator Inhibitor ◽  
Venous Stasis ◽  
Microvascular Thrombosis ◽  
Duct Ligation

SummaryMicrovascular thrombosis is considered an important pathogenetic factor in renal failure associated with obstructive jaundice but the mechanisms leading to fibrin deposition are still unknown. The plasma levels of plasminogen activator inhibitor (PAI) in 29 patients with obstructive jaundice were found significantly increased as compared to 20 nonjaundiced patients. Fibrin autography of plasma supplemented with tissue plasminogen activator (t-PA) revealed that in icteric samples most of the added activator migrated with an apparent Mr of 100 kDa, corresponding to t-PA-PAI complex, whereas in control samples virtually all t-PA migrated as free enzyme. PAI activity detected in icteric samples is similar to the endothelial type PAI since it is neutralized by a monoclonal antibody against PAI-1.Venous stasis in jaundiced patients was neither associated with an increase in blood fibrinolytic activity nor with a decrease in PAI activity. Immunologic assay showed that t-PA release was impaired in 3 out of 4 patients. In controls, venous occlusion induced an increase in both fibrinolytic activity and t-PA antigen and a reduction in PAI activity. Bile duct recanalization in jaundiced patients subjected to surgery was accompanied by a decrease in plasma PAI activity which paralleled the decrease in serum bilirubin levels. In nonjaundiced patients, surgical treatment did not cause significant changes in either parameter. Rabbits made icteric by bile duct ligation showed an early and progressive increase in plasma PAI activity indicating that obstructive jaundice itself causes the elevation of circulating PAI. It is concluded that obstructive jaundice is associated with a severe impairment of fibrinolysis which might contribute to microvascular thrombosis and renal failure.

A new method for the experimental induction of secundary biliary cirrhosis in wistar rats

2001 ◽  
Vol 16 (2) ◽  
pp. 75-81 ◽  
Author(s):  
Gracinda De Lourdes Jorge ◽  
Luiz Sergio Leonardi ◽  
Ilka de Fatima Santana Ferreira Boin ◽  
Orlando de Castro e Silva Jr ◽  
Cecilia Amelia Fazzio Escanhoela
Keyword(s):  
Bile Duct ◽  
Morphological Study ◽  
Wistar Rats ◽  
Hepatic Duct ◽  
Control Group ◽  
Sham Operation ◽  
Biliary Cirrhosis ◽  
Technical Failure ◽  
Duct Obstruction ◽  
Duct Ligation

The aim of this study was to describe a method for the induction of experimental secondary biliary fibrosis (SBF). Forty-seven Wistar rats were submitted to hepatic duct obstruction (OB group) for thirty days without ligature, section or cannulization causing interruption of biliary flow. This technique was carried out by simple traction of the bile duct passing it through the xiphoid appendix. Nine rats were submitted to a sham operation for bile duct stricture and seven rats comprised the control group. Blood samples were collected for the measurement of total bilirubin (TB), alkaline phosphatase (AP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Liver fragments were removed for morphological study. Thirty days after surgery TB, AP, ALT and AST levels were significantly increased in the hepatic duct ligation group compared to the sham operated group and the presence of SBF in the OB group was confirmed by morphological study of the liver. There was technical failure in 31.92% cases. The survival was 100% at fifteen days and 82.97% at the end of the experiment. We concluded that this simple surgical technique may be used to study the consequence of bile duct obstruction which could be a reversible process depending on the obstruction time. This technique can be carried out from cholestasis to fibrosis.

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