Background: Hepatic cirrhosis is associated with a variety of hemodynamic and hydrodynamic
abnormalities, including renal dysfunction with salt and water retention leading to ascites
and dilutional hyponatremia.
Objective: In the present study, a proteomic analysis of the kidney of rats subjected to bile duct
ligation (BDL) has been carried out in order to identify the proteins altered under this condition.
Method: The experiments were performed at the fourth week after BDL, and the protein mixtures
were separated by two-dimensional gel electrophoresis using the differential in-gel system
(DIGE). An internal standard composed of equal amounts of the above 12 extracts was labeled
with Cy2, and loaded onto six gels.
Results: More than 4,000 proteins were labeled and numbered, and around 60 proteins were differentially
expressed in the kidneys of BDL rats as compared to the controls, as analyzed by De-
Cyder software. The respective spots were excised and digested with trypsin for MALDITOF/
TOF peptide mass fingerprinting analysis. Some of the proteins down-regulated in the kidney
of the BDL rats were Ezrin, Moesin and Regucalcin, whereas Annexin-4, Cathepsin B and
Heat Shock Proteins were significantly up-regulated.
Discussion: The relationship of these proteins to the systemic and renal abnormalities seen in
BDL rats is discussed.