Expression of VEGF, GFAP, and BDNF genes in the brain of rats after fractionated γ-irradiation according to different protocols.

ABSTRACT

The expression of VEGF, GFAP, and BDNF genes in the nervous tissue changed on weeks 4, 8, and 12 after fractionated irradiation of the brain according to different protocols in a fixed total dose of 36 Gy. The expression of VEGF gene decreased in the prefrontal cortex and hippocampus after 4 and 8 weeks. After week 12, the expression of VEGF normalized in the prefrontal cortex and remained low in the hippocampus. The expression of GFAP gene was maximum in the prefrontal cortex after week 4 and returned to normal in week 12. In the hippocampus, the expression of GFAP was low only after week 12. The expression of BDNF gene was reduced only during the week 8 and this decrease was directly proportional to the single dose. Hence, fractionated γ-irradiation with fixed total dose differently modified gene expression in the nervous tissue.