关键词: 神经发生；蛛网膜下腔出血；早期脑损伤；间接免疫荧光法；Wnt3a；&beta, -连环蛋白；散乱蛋白-1

Abstract: Objective  To investigate the effects and possible mechanisms of Wnt3a on the neurogenesis in rats during early brain injury after subarachnoid hemorrhage (SAH). Methods  A total of 70 adult male SD rats were randomly divided into 7 groups: the sham operation group, SAH group, Wnt3a Ⅰ group, Wnt3a Ⅱ group, Wnt3a Ⅲ group, Wnt3a Ⅳ group and DKK-1 group. The SAH model was established by injecting autologous blood into cisterna magna. An immunofluorescence technique was used to detect neurogenesis by investigating the BrdU-positive cells located in the dentate gyrus of the hippocampus of rats. Dishevelled-1(Dvl-1) and β-catenin expressions were detected with Western blotting. Results  After injection of 5, 10, 20 and 40μg/mL Wnt3a into the cisterna magna, the percentages of BrdU-positive cells gradually increased (P<0.05). The expressions of Dvl-1 and β-catenin protein were also upregulated in a dose-dependant manner (P<0.05). After injection of DKK-1 as an inhibitor of classical Wnt signaling pathway, the percentage of BrdU-positive cells markedly decreased (P<0.05), and the activities of Dvl-1 and β-catenin were inhibited (P<0.05). Conclusion  Wnt3a may have the potential to promote neurogenesis by activating canonical Wnt-signaling pathway during early brain injury after SAH, which can contribute to the protection and reparation of the central nervous system.

Key words: Dishevelled-1, Subarachnoid hemorrhage, Indirect Immunofluorescence, Wnt3a, β-catenin; , Early brain injury,  Neurogenesis