Department of Cell Biology, Oklahoma Center of Neuroscience, University of Oklahoma Health Science Center, BRC, Room 266, 975 NE 10th Street, Oklahoma City, OK 73104, USA.
Exp Eye Res. 2013 Sep;114:120-7. doi: 10.1016/j.exer.2013.03.008. Epub 2013 Mar 23.
Emmetropization is a vision dependent mechanism that attempts to minimize refractive error through coordinated growth of the cornea, lens and sclera such that the axial length matches the focal length of the eye. It is generally accepted that this visually guided eye growth is controlled via a cascade of locally generated chemical events that are initiated in the retina and ultimately cause changes in scleral extracellular matrix (ECM) remodeling which lead to changes in eye size and refraction. Of much interest, therefore, are the molecular mechanisms that underpin emmetropization and visually guided ocular growth. The choroid, a highly vascularized layer located between the retina and the sclera is uniquely situated to relay retina-derived signals to the sclera to effect changes in ECM synthesis and ocular size. Studies initiated by Josh Wallman clearly demonstrate that the choroid plays an active role in emmetropization, both by modulation of its thickness to adjust the retina to the focal plane of the eye (choroidal accommodation), and well as through the release of growth factors that have the potential to regulate scleral extracellular matrix remodeling. His discoveries prompted numerous investigations on the molecular composition of the choroid and changes in gene expression associated with visually guided ocular growth. This article will review molecular and functional studies of the choroid to provide support for the hypothesis that the choroid is a source of sclera growth regulators that effect changes in ocular growth in response to visual stimuli.
正视化是一种依赖视觉的机制，它试图通过角膜、晶状体和巩膜的协调生长来最小化屈光不正，使得眼轴与眼睛的焦距相匹配。人们普遍认为，这种视觉引导的眼球生长是通过视网膜中局部产生的化学事件级联反应来控制的，这些事件最终导致巩膜细胞外基质（ECM）重塑的变化，从而导致眼睛大小和屈光度的变化。因此，眼球正视化和视觉引导的眼球生长的分子机制非常引人关注。脉络膜是一种位于视网膜和巩膜之间的高度血管化的层，它的位置非常特殊，可以将视网膜衍生的信号传递到巩膜，从而影响 ECM 合成和眼球大小的变化。乔希·沃尔曼（Josh Wallman）的研究清楚地表明，脉络膜在正视化中发挥着积极的作用，它可以通过调节脉络膜的厚度来调整视网膜与眼睛焦点平面的距离（脉络膜调节），也可以通过释放生长因子来调节巩膜细胞外基质的重塑。他的发现促使人们对脉络膜的分子组成以及与视觉引导的眼球生长相关的基因表达变化进行了大量研究。本文将综述脉络膜的分子和功能研究，为脉络膜是产生调节巩膜生长的因子的假说提供支持，这些因子可以响应视觉刺激调节眼球生长。
