STRUCTURAL BASIS OF AMBLYOPIA IN MONKEYS & HUMANS

猴子弱视的结构基础

• 批准号: 6277969
• 负责人: JONATHAN C HORTON
• 金额: $ 5.21万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 1999-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6277969
• 关键词: Mammalia; Primates; ear; surgery

Significance Amblyopia (lazy eye) causes visual loss in 2% of the American population. Our research is directed at elucidating structural changes in the primate visual cortex which occur from visual deprivation. Objectives Visual deprivation induced by monocular eyelid suture, a laboratory model for congenital cataract, results in shrinkage of ocular dominance columns serving the closed eye. We performed monocular suture in macaques at ages 1,3,5,7, and 12 weeks to define the critical period for plasticity of ocular dominance columns. Results After a minimum survival of 8 months, complete montages of [3H]proline-labelled columns were reconstructed from flat-mounts of striate cortex in both hemispheres. Visual deprivation induced the columns throughout V1 to retract the same distance from their original borders in layer IVc(. At the earliest age we tested (1 week), visual deprivation reduced the columns to fragments. These fragments always coincided with a cytochrome oxidase patch, or a short string of patches, in the upper layers. More severe column shrinkage occurred in layer IVc( (parvo) than layer IVca (magno). The geniculate input to the patches in layer III (konio) appeared normal after deprivation, despite loss of CO activity. Surprisingly, the blind spot representation of the open eye was shrunken by monocular deprivation, although binocular competition is absent in this region. We found that eyelid suture at age 1 week caused the most severe column shrinkage. With suture at later ages, the degree of column shrinkage showed a progressive decline. This implies that primate visual cortex is most vulnerable to deprivation during the first weeks of life, and should provide further impetus for treatment of children with congenital cataract at the earliest possible age. Future Directions Analysis of the changes in connections between cortical layers which occur in amblyopia and initiation of new studies regarding the cortical basis of strabismus (crossed eyes). KEYWORDS ocular dominance column, critical period, amblyopia, visual deprivation, cytochrome oxidase patch, flat-mount, striate cortex, strabismus

意义上的弱视（懒惰的眼睛）导致2％的视觉丧失 美国人口。 我们的研究旨在阐明 灵长类动物视觉皮层的结构变化 视觉剥夺。 目标视觉剥夺由 单眼眼睑缝合线，一种先天性白内障的实验室模型， 导致封闭式的眼部优势柱的收缩 眼睛。 我们在1,3,5,7的猕猴中进行了单眼缝合线，然后 12周来定义眼睛可塑性的关键时期 优势柱。 最低生存期8个月后的结果， 重建了[3H]脯氨酸标记的柱的完整蒙太奇 来自两个半球的平板横向皮质。 视觉的 剥夺诱导整个V1的色谱柱缩回相同 距离其原始边界的距离IVC（最早 我们测试的年龄（1周），视觉剥夺将列减少到 碎片。 这些片段总是与细胞色素氧化酶一致 贴片，或上层中的一条短串。 更严重 列收缩发生在IVC层中（（Parvo），而不是IVCA层 （Magno）。 第三层（Konio）中斑块的遗传输入 尽管剥夺了CO活动，但在剥夺后还是正常的。 令人惊讶的是，睁大眼睛的盲点表示是 尽管双眼竞争是 该地区不存在。 我们发现1周的眼睑缝合 引起最严重的柱收缩。 随后的缝合线， 色谱柱收缩程度显示出逐渐下降。 这 暗示着灵长类动物视觉皮层最容易受到剥夺 在生命的头几周，应为 最早对先天性白内障儿童的治疗 可能的年龄。 对变化的未来方向分析 在弱视和 启动有关斜视的皮质基础的新研究 （交叉的眼睛）。 关键字眼优势列，关键时期， 弱视，视觉剥夺，细胞色素氧化酶贴片，扁平化型 条纹皮质，斜视