Reduced antioxidant level and increased oxidative damage in intact liver lobes during ischaemia-reperfusion.
OBJECTIVE
To determine whether increased blood flow of the liver can cause oxidative stress and hepatocyte damage, and to elaborate methods suitable for measuring the antioxidant defence during hepatic surgery on rat model.


METHODS
In nembutal narcosis, the left lateral and the medial lobes of the liver were clipped for 45 min to make the total blood supply flow through the other lobes. Total antioxidant status, glutathione peroxidase and superoxide dysmutase activity, as well as the concentrations of diene conjugates and free sulphydril groups, H-donating ability and reducing power of the liver samples were determined. Chemiluminescent intensity of the liver was also measured. Metal ions (Al, Ca, Cu, Fe, Mg, Mn, Zn) and P and S concentrations of the liver were determined with an inductively coupled plasma optical emission spectrometer and Se content was measured by cathodic stripping voltammetry.


RESULTS
Glutathione peroxidase and superoxide dysmutase activities of the liver decreased significantly in the hyperemia group compared to those observed in the sham operated group. The level of total antioxidant status was also significantly lower in the hyperemia group. H-donating ability, reducing power and free sulphydril group concentration showed the same tendency. A significant correlation (P<0.05) was found between the changes in non-specific antioxidant activities. This pointed to simultaneous activity of the antioxidant defence system. Al, Cu, Mn, Zn, and S were lower in the hyperemia group than in the sham operated group when the levels of Ca, Fe, Mg, Se and P ions were higher during hyperemia.


CONCLUSIONS
Oxidative stress is one of the main factors for the injury of intact liver lobes during ischaemia-reperfusion.
Department of Medicine, Semmelweis University, H-1088 Budapest, Szentkirályiu. 46., Hungary.
László
L
Váli
Gabriella
G
Taba
Klára
K
Szentmihályi
Hedvig
H
Fébel
Tímea
T
Kurucz
Zsolt
Z
Pallai
Péter
P
Kupcsulik
Anna
A
Blázovics
D000704:Analysis of Variance; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D004602:Elements; D005979:Glutathione Peroxidase / Q000378:metabolism; D006940:Hyperemia / Q000378:metabolism / Q000473:pathology; D008099:Liver / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology*; D008102:Liver Circulation; D008297:Male; D018384:Oxidative Stress; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000378:metabolism* / Q000473:pathology; D013482:Superoxide Dismutase / Q000378:metabolism
D000975:Antioxidants; D004602:Elements; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase