血管内皮生长因子-B在弱视大鼠眼优势柱可塑性中的神经保护作用

The neuroprotective effect of vascular endothelial growth factor-B on the plasticity of dominant column in amblyopic rats

目的血管内皮生长因子-B(VEGF-B)能够阻止幼年Long-Evans单眼剥夺弱视大鼠初级视皮层眼优势柱进一步的漂移,本文旨在探讨VEGF-B及其受体VEGFR-1在正常及单眼剥夺弱视Long-Evans大鼠视皮层17区的表达差异及其在此过程中VEGF-B对视神经的保护作用。方法21日龄Long-Evans大鼠共26只,随机分成4组,正常组(5只)、单眼剥夺组(7只)、VEGF-B微注射联合单眼剥夺组(7只)、人工脑脊液微注射联合单眼剥夺组(7只)。单眼剥夺造模后,利用神经电生理方法检测4组大鼠初级视皮层眼优势柱的分布优势,应用免疫组织化学法测定正常组及单眼剥夺弱视组大鼠视皮层17区VEGF-B及其受体VEGFR-1的表达差异。结果单眼剥夺组及人工脑脊液微注射联合单眼剥夺组大鼠视皮层眼优势柱的分布均为同侧眼优势,而VEGF-B微注射联合单眼剥夺组大鼠视皮层眼优势柱的分布为对侧眼占优势,与正常组相同。剥夺组视皮层VEGF-B及其受体VEGFR-1阳性细胞密度值及积分光密度值均较正常组减少,差异有统计学意义。结论在Long-Evans大鼠视觉发育敏感期内因单眼剥夺造成形觉剥夺性弱视的幼鼠视皮层17区的VEGF-B及其受体VEGFR-1表达减弱。VEGF-B联合单眼剥夺弱视幼鼠脑室给药干预治疗后,单眼剥夺弱视的大鼠眼优势柱发生了漂移,与正常幼鼠眼优势柱相同,因此,VEGF-B及其受体VEGFR-1参与了Long-Evans大鼠初级视皮层眼优势柱可塑性发育,并且在此过程中具有神经保护的作用。

Objective Explore the different expression of vascular endothelial growth factor-B(VEGF-B)and its receptor VEGFR-1 in the 17 area of the visual cortex of normal and monocular deprived amblyopia Long-Evans rats and the neuroprotective effect of VEGF-B on the optic nerve in this process.Methods 21 day-old Long-Evans rats were randomly divided into four groups:normal group(5 rats),monocular deprived amblyopia MD group(7 rats),VEGF-B microinjection combined with MD group(7 rats),and artificial cerebrospinal fluid(aCSF)microinjection combined with MD group(7 rats).After monocular deprivation modeling,the distribution advantages of the ocular dominant columns in the primary visual cortex of the rats in four groups were detected by neuroelectrophysiological methods,and the expression differences of VEGF-B and VEGFR-1 in the visual cortex of rats in the normal group and MD group was measured by immunohistochemistry.Results The distribution of dominant ocular columns in the visual cortex of rats in the MD group and the aCFS+MD group were ipsilateral ocular dominance,while the VEGF-B+MD group was contralateral,which is the same as the normal group.The densities and integral optical density values of VEGF-B and its receptor VEGFR-1 in the visual cortex of the MD group were reduced compared with those in the normal group,and the differences had statistical significance(P<0.05).Conclusion In the sensitive period of Long-Evans rats visual development,the expression of VEGF-B and its receptor VEGFR-1 in the visual cortex of young rats with deprivation amblyopia caused by MD was reduced.After VEGF-B combined with intracerebroventricular administration of MD amblyopic rats,the ocular dominance column of MD rats drifted,which is the same as the ocular dominance column of normal pups.Therefore,VEGF-B and its receptor VEGFR-1 participat in the plasticity development of the dominant ocular column in the primary visual cortex of Long-Evans rats,and has a neuroprotective effect in this process.