title: Changes in the pool of bile acids in hepatocyte nuclei during rat liver regeneration.
abstract: OBJECTIVE
  To investigate changes in nuclear bile acids (BAs) during rat liver regeneration.
  
  
  METHODS
  Nuclei were isolated from control rat livers and after two-thirds partial hepatectomy (PH). BAs in bile, liver homogenate and nuclei were measured by gas chromatography-mass spectrometry. Nuclear translocation of radiolabeled BAs was determined using fresh isolated hepatocytes from control donors.
  
  
  RESULTS
  Liver BA concentrations were transiently reduced after PH. Relative increases in: -MCA at 1 day, deoxycholic acid at 7 days and cholic acid (CA) at 3 and 14 days were found. Nuclear BAs accounted for <0.5% of liver BAs. Contamination with cytosolic BAs during nuclei isolation was <4%. Unconjugated- and conjugated-CA were able to reach the nucleus with similar efficiency. The pattern of nuclear BAs--CA (80%) and ursodeoxycholic acid (UDCA) (8.5%) being the most abundant--did not match that found in liver or bile. A transient decrease in CA/UDCA ratio, in absence of significant change in total BA content, was observed in nuclei after PH. "Flat" BA species were only detected in homogenate, but not in nuclei, at 1 day after PH.
  
  
  CONCLUSIONS
  BA pool in nuclei of rat hepatocytes, whose composition is different to that of total liver BA pool, undergoes important changes during liver regeneration.
authors.affiliation: Department of Physiology and Pharmacology, University of Salamanca, Campus Miguel de Unamuno, E.I.D. S-09 37007, Salamanca, Spain.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Monte
authors.forename: Maria C
authors.initials: MC
authors.lastname: Martinez-Diez
authors.forename: Mohamad Y
authors.initials: MY
authors.lastname: El-Mir
authors.forename: Maria E
authors.initials: ME
authors.lastname: Mendoza
authors.forename: Pilar
authors.initials: P
authors.lastname: Bravo
authors.forename: Oriol
authors.initials: O
authors.lastname: Bachs
authors.forename: Jose J G
authors.initials: JJ
authors.lastname: Marin
mesh_terms: D000818:Animals; D001646:Bile / Q000378:metabolism; D001647:Bile Acids and Salts / Q000378:metabolism*; D001692:Biological Transport; D002467:Cell Nucleus / Q000378:metabolism*; D019826:Cholic Acid / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism*; D008115:Liver Regeneration / Q000502:physiology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001647:Bile Acids and Salts; D019826:Cholic Acid