K. Yamaoka et al., EFFECTS OF LOW-DOSE X-RAY-IRRADIATION ON BIOMEMBRANE IN BRAIN CORTEX OF AGED RATS, Free radical biology & medicine, 16(4), 1994, pp. 529-534
We previously found that low-dose X-ray irradiation or radon (weak alp
ha-ray) inhalation increases SOD activities and reduces lipid peroxide
levels in various organs of 7-week-old rats or rabbits. In this study
, we examined how the changes of SOD activity, lipid peroxide level, a
nd membrane fluidity of the cerebral cortex in aged male Wistar rats (
65 and 91 weeks old) were affected by low-dose X-ray irradiation (100
cGy or under) compared with those in 7-week-old rats, to elucidate the
mechanism of aging inhibition. The following results were obtained: A
lthough radiation sensitivity was observed to decreases with age, low-
dose irradiation changed the Mn-SOD activity, lipid peroxide level, an
d membrane protein fluidity parameter of the cerebral cortex in the ag
ed rats to be closer to those in the youth. These findings suggest tha
t the increased SOD activity induced by low-dose irradiation enhances
biomembrane functions, and that the decrease of lipid peroxide level e
nhances the membrane protein fluidity.