血管活性肠肽在单眼视觉剥夺性弱视幼猫外侧膝状体中的表达

Expression of vasoactive intestinal peptide in the lateral geniculate body of kittens with monocular deprivation amblyopia

目的比较视觉剥夺性弱视幼猫和正常幼猫外侧膝状体中血管活性肠肽(VIP)的表达差异,探讨外侧膝状体中VIP在弱视发病中的意义。方法健康3周龄幼猫30只,排除屈光介质混浊及眼底异常。随机分为对照组和剥夺组,每组15只,均饲养在光照充足环境中。麻醉剥夺组幼猫后,予以黑色不透光眼罩遮盖右眼。定期行图形视觉诱发电位(PVEP)检测。6周龄时经PVEP检测弱视模型复制成功后,根据猫脑Sinder立体定位图,切取对照组及剥夺组幼猫的右侧外侧膝状体,分别行VIP免疫组织化学和VIP mRNA原位杂交。利用数据分析软件统计阳性细胞数和阳性细胞数平均光密度值。结果6周龄时,剥夺组右眼P100波潜伏期较对照组右眼和剥夺组左眼延长(P<0.05),而振幅降低(P<0.05)。剥夺组VIP免疫组织化学和VIP mRNA原位杂交的阳性细胞数及阳性细胞平均光密度值降低(P<0.05)。结论视觉剥夺导致外侧膝状体中VIP表达下降,VIP减少又影响外侧膝状体中神经元功能的正常表达,表明VIP在视觉发育中有重要作用。

Obiective To investigate the significance of vasoactive intestinal peptide(VIP)in the lateral geniculate corpus in the pathogenesis of amblyopia.Method Thirty healthy 3-week-old domestic cats that had excluded turbidity of the refractive medium and abnormal fundus were randomly divided into normal control group(15 rats)and monocular deprivation group(15 rats),and were housed in a well-lit environment.After the kittens in monocular deprivation group was anesthetized,the right eye was covered with a black eyepatch,and the regular pattern visual evoked potential(PVEP)detection was performed.The use of PVEP to detect whether the amblyopia model was successfully established was at 6 weeks of age in kittens.The right lateral geniculate bodies of the control group and the deprivation group were excised according to the Sinder stereotactic map of the cat brain,and VIP immunohistochemistry and VIP mRNA in situ hybridization were performed respectively.The average optical density values of positive cells and the number of positive cells were counted using data analysis software.Result At 6 weeks of age in kittens,the P100 wave latency of the right eye of monocular deprivation group was longer than that of the right eye of the control group(P<0.05),while the amplitude decreased(P<0.05).The number of positive cells and the average optical density of positive cells obtained by VIP immunohistochemistry and VIP mRNA in situ hybridization were decreased in monocular deprivation group(P<0.05).Conclusion Visual deprivation amblyopia leads to a decrease in the expression of VIP in the lateral geniculate body,and the reduction of VIP affects the normal functional expression of neurons in the lateral geniculate body,which proves that VIP plays an important role in visual development.