ABSTRACT
Background and purpose:Radiotherapy is one of the main treatment methods for brain tumor patients, but neurotoxicity was observed frequently. Because of the confounding factors in clinical data, it’s hard to summarize the characteristic of neurological changes after brain irradiation. This study used the brain irradiation injury model of rats to test whether brain irradiation change the mood and memory.Methods:Whole brain of SD rats (6-8 weeks old) was exposed to 22 Gy radiation. Open ifeld and elevated plus maze was used to assess the anxiety of rats, passive avoidance was used to assess the mood memory, and novel place recognition was used to assess the spatial memory at 1 month or 10 months after brain irradiation.Results:At 1 month post irradiation, rats moved with less distance and entrance to the central zone of open ifeld with less time, explored the open and closed arms with less time and the exploration of open arms also decreased, entered the darkroom more rapidly during the test phase of passive avoidance, and lose the interest to explore the novel place during novel place recognition. At 10 months post irradiation, rats exhibited similarly with control group during open ifeld and elevated plus maze test, but still entered the darkroom more rapidly during the test phase of passive avoidance, and lose the interest to explore the novel place during novel place recognition.Conclusion:Brain irradiation could decrease the locomotor activity, increase the anxiety mood, reduce the mood and spatial memory; mood dysfunction induced by brain irradiation could restore, but memory impairments would be long-standing.
ABSTRACT
Objective To investigate the change of S-100B in serum in rats at varions times after exposure to different whole-brain irradiation doses and to explore the characteristics of the S-100B change in early radiation-induced brain injuries. Methods A model of brain radlation-induced injuries was estabhshed in the rat after whole-brain irradiation with a single dose of 2, 10, or 30 Gy of 4 MeV electron. The concentration of S-100B in serum was detected by means of enzyme-linked immunoserbent assay (ELISA) at different time points (1,6,12,24,3 days, 1 week, 1 month) after exposure. Results In terms of measuring time points, the serum concentration in all groups reached the fwst peak 6 hours after irradiation, declined after 12 hours, rose again after 24 hours, and started to decline again until the last time point (1 month), with the exception of the 2 Gy group, which reached the second peak at 3 days after irradiation. Conclusions The S-100B serum concentration was changed in the rats after whale-brain irradiation and these changes are positively related to the irradiation amount. It seems that the higher the dose, the higher the serum concentration and the differences between the dose groups are significant (via multiple regression models). The S-100B may be a valuable serum marker for the brain irradiation injury.