title: Hepatocyte polarity and the peroxisomal compartment: a comparative study.
abstract: In search of factors that regulate the phenotype of the peroxisomal compartment in wild-type liver parenchymal cells, we compared hepatocyte polarity to peroxisome differentiation, using adult liver as the standard. Differentiation parameters were evaluated in a three-dimensional culture model (spheroid), in 'sandwich' and monolayer primary hepatocyte cultures, and in 15.5 and 18.5-day-old foetal rat liver. Peroxisomes, studied by immunohistochemistry, enzyme histochemistry, and catalase specific activity, were better differentiated depending on foetal age (day 18.5 > day 15.5) and culture type (spheroid > sandwich > monolayer). The hepatocyte polarity markers ATP-, ADP-, and AMP-hydrolysing activities were, in all models, mislocalized at the lateral plasma membrane, whereas in contrast the multidrug resistance-associated protein 2 (mrp2) antigen was always correctly immunolocalized at the apical membrane domain. In cultures, the correct secretion of fluorescein (mrp2-mediated) into bile canaliculi was observed. Bile canaliculi (branching, ultrastructure and immunolocalization of the tight-junction associated protein ZO-1), were better differentiated in 18.5 than in 15.5-day-old foetal liver and in spheroid > sandwich > monolayer cultures. Our results show a parallelism between changes of the peroxisomal compartment and bile canalicular structure together with mrp2-mediated secretory function. Distinct polarization characteristics do not necessarily change simultaneously, suggesting different regulatory mechanisms.
authors.affiliation: Department of Human Anatomy, Embryology, Histology, and Medical Physics, Ghent University, Godshuizenlaan 4, B-9000 Gent, Belgium.
authors.forename: Marianne
authors.initials: M
authors.lastname: Depreter
authors.forename: Tracy
authors.initials: T
authors.lastname: Walker
authors.forename: Karen
authors.initials: K
authors.lastname: De Smet
authors.forename: Sonja
authors.initials: S
authors.lastname: Beken
authors.forename: Ingrid
authors.initials: I
authors.lastname: Kerckaert
authors.forename: Vera
authors.initials: V
authors.lastname: Rogiers
authors.forename: Frank
authors.initials: F
authors.lastname: Roels
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000249:Adenosine Monophosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000418:Albumins / Q000378:metabolism; D000818:Animals; D001648:Bile Canaliculi / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure; D002374:Catalase / Q000378:metabolism; D016764:Cell Polarity / Q000502:physiology*; D002478:Cells, Cultured; D005260:Female; D019793:Fluorescein; D022781:Hepatocytes / Q000502:physiology* / Q000648:ultrastructure; D007150:Immunohistochemistry; D008112:Liver Glycogen / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D026901:Membrane Transport Proteins; D008854:Microscopy, Electron; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000378:metabolism; D020675:Peroxisomes / Q000502:physiology* / Q000648:ultrastructure; D010750:Phosphoproteins / Q000378:metabolism; D011247:Pregnancy; D051381:Rats; D019108:Tight Junctions / Q000648:ultrastructure; D062826:Zonula Occludens-1 Protein
chemical_list: D000244:Adenosine Diphosphate; D000249:Adenosine Monophosphate; D000255:Adenosine Triphosphate; D000418:Albumins; D002374:Catalase; D019793:Fluorescein; D008112:Liver Glycogen; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D010750:Phosphoproteins; D062826:Zonula Occludens-1 Protein; C000715087:ABCC2 protein, human; C569042:TJP1 protein, human; C569044:Tjp1 protein, rat