The activity of ornithine transcarbamoylase and arginase during mechanical jaundice in the rat model.
BACKGROUND
The pathogenesis of morbidity and mortality associated with intervention of the biliary system in patients with obstructive jaundice is unknown. Mechanical jaundice initiates the development of morphological changes in hepatocytes with concomitant disturbances in metabolism. These are followed by changes in enzyme activity in hepatocytes and peripheral blood.


METHODS
Wistar rats were divided into three groups: group 1, sham-operated controls; group 2, rats with permanent jaundice; and group 3, rats with temporary mechanical jaundice. The animals were examined at 2 weeks (groups A), 4 weeks (groups B) and 6 weeks (groups C) after surgery. We explored the impact of induced mechanical jaundice on the activity of selected urea cycle enzymes (arginase [E.C.3.5.3.1] and ornithine transcarbamoylase (OTC) [E.C.2.1.3.3]).


RESULTS
Mechanical jaundice was found to induce changes in hepatocytic metabolism, which in turn led to disturbances in the urea cycle and the process of transamination. After relief of the mechanical jaundice (recanalization of the common bile duct), the urea cycle activity in the liver was greatly increased despite the normalization of the basic biochemical indices.


CONCLUSIONS
The results of the experiment confirmed the hypothesis that long-term mechanical jaundice causes lasting disturbances in hepatocytic metabolism. We conclude that the rate of nitrogen metabolism is higher after recanalization of the bile duct.
Beck
Brygida
B
Department of Biochemistry, Medical University of Silesia, Zabrze, Poland. bbeck@slam.katowice.pl
Ciszek
Marian
M
Polaniak
Renata
R
Beyga
Zbigniew
Z
Król
Wojciech
W
Drozdz
Marek
M
Shani
Jashovam
J
D000469:Alkaline Phosphatase / Q000097:blood; D000818:Animals; D001119:Arginase / Q000378:metabolism*; D001663:Bilirubin / Q000097:blood; D004195:Disease Models, Animal; D041781:Jaundice, Obstructive / Q000097:blood / Q000201:enzymology*; D008297:Male; D009954:Ornithine Carbamoyltransferase / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014508:Urea / Q000378:metabolism
D014508:Urea; D009954:Ornithine Carbamoyltransferase; D000469:Alkaline Phosphatase; D001119:Arginase; D001663:Bilirubin