Increased CD147 and MMP-9 expression in the normal rat brain after gamma irradiation

Radiation-induced vascular injury is a major complication of gamma knife surgery (gks). previous studies have shown that cd147 and mmp-9 are closely associated with vascular remodeling and pathological angiogenesis. thus,we analysed changes in cd147 and mmp-9 expression in the cerebral cortex to investigate the correlation between cd147 and mmp-9 in the rat following gks. adult male wistar rats were subjected to gks at a maximum dose of 75 gy and then euthanized 1 to 12 weeks later. using immunohistochemistry and western blot analysis,we found that cd147 and mmp-9 expression were markedly upregulated in the target area 8-12 weeks after gks when compared with the control group. immunofluorescent double staining demonstrated that cd147 signals colocalized with cd31,gfap and mmp-9-positive cells. importantly,cd147 levels correlated with increased mmp-9 expression in irradiated brain tissue. for the first time,these data demonstrate a potential relationship between cd147 and mmp-9 following gks. in addition,our study also suggests that cd147 and mmp-9 may play a role in vascular injury after gks. © the author 2012. published by oxford university press on behalf of the japan radiation research society and japanese society for therapeutic radiology and oncology.