Effects of two different high doses of irradiation on antioxidant system in the liver of guinea pigs.
OBJECTIVE
To examine the state of the oxidant-antioxidant system in the liver of guinea pig caused by high doses of ionizing radiation in the early period.


METHODS
The research was carried out on guinea pigs irradiated with the doses of 8 Gy (group 2) or 15 Gy (group 3) (single dose/whole body) in comparison with control group (group 1). The levels of thiobarbituric acid reactive substances (TBARS) and glutathione (GSH), the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and the levels of selenium in the liver were measured.


RESULTS
TBARS levels in the irradiated animals were markedly higher than those in controls. In group 3, GSH levels and GSH-Px activity were significantly increased while activity of SOD and CAT were significantly decreased compared to groups 1 and 2. Liver selenium levels were not influenced by irradiation.


CONCLUSIONS
The data have shown that gamma-irradiation at the doses of 8 Gy or 15 Gy results in significant increase in free radical formation while antioxidant enzymes were affected only at a dose of 15 Gy.
Guney
Yildiz
Y
Gazi University Medical Faculty Department of Biochemistry, Ankara, Turkey.
Bukan
Neslihan
N
Dizman
Aysen
A
Hicsonmez
Ayse
A
Bilgihan
Ayse
A
D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays / Q000009:adverse effects*; D005979:Glutathione Peroxidase / Q000378:metabolism; D006168:Guinea Pigs; D008099:Liver / Q000201:enzymology / Q000378:metabolism / Q000528:radiation effects*; D018384:Oxidative Stress / Q000528:radiation effects*; D011829:Radiation Dosage; D012643:Selenium / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014916:Whole-Body Irradiation
D000975:Antioxidants; D017392:Thiobarbituric Acid Reactive Substances; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D012643:Selenium