Comparison of Normobaric Oxygen and Hyperbaric Oxygen on Angiogenesis in the Brain of Adult Rats with Cerebral Ischemia-Reperfusion Injury

Objective: To investigate the difference between normobaric oxygen(NBO) and hyperbaric oxygen(HBO) on angiogenesis in the brain of adult rats with cerebral ischemia-reperfusion injury.Methods: Adult male Sprague-Dawley(SD) rats were randomly divided into three groups: the sham surgery(SS) group,the NBO group and the HBO group.Each group was randomly divided into three subgroups: the 3 days group,the 7 days group and the 10 days group.Middle cerebral artery occlusion(MCAO) was performed to the NBO and HBO groups to develop the animal model.1.5 hours later,reperfusion was made.Then,the NBO group received NBO treatment,and the HBO group received HBO treatment.All the rats were sacrificed respectively on day 3,7,10;Cerebral samples were collected and prepared to sections.The sections were treated with immunohistochemical staining with the following antibody: Vascular endothelial growth factor(VEGF),VEGF receptor-1(Flt-1),CD34.The changes in ischemia region were detected under the optical microscope,and the pictures were taken.Results: Compared with those in the SS group,numbers of VEGF and Flt-1 and CD34 positive cells increased markedly in the NBO group(P0.05).The numbers of VEGF and Flt-1 and CD34 positive cells increased significantly on day 7 and day 10,following HBO treatment compared with those in the NBO group(P0.05).Conclusions: HBO therapy is better to promote angiogenesis in the brain of adult rats with ischemia-reperfusion injury than NBO treatment.