Ocular diurnal rhythms and eye growth

眼昼节律和眼睛生长

• 批准号: 6616827
• 负责人: DEBORA L NICKLA
• 金额: $ 18.48万
• 依托单位: NEW ENGLAND COLLEGE OF OPTOMETRY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6616827
• 关键词: biological signal transduction; chickens; circadian rhythms; glycoprotein biosynthesis; growth /development; membrane reconstitution /synthesis; molecular film; myopia; retinoate; sclera; ultrasonography

DESCRIPTION (provided by applicant): In the United States, myopia affects nearly 25 percent of the population, while in certain other developed countries the proportion of the population affected increases to 80 percent or more. Pathological myopia is also a leading cause of blindness. Therefore, understanding the mechanisms underlying the regulation of ocular growth is critical towards understanding how and why it goes awry in eyes that develop ametropias, and might lead to the development of new therapies. Recent work has indicated that changes in the rate of ocular growth are associated with alterations in ocular circadian rhythms. The work proposed here seeks to extend these original observations, to better understand the mechanisms underlying these effects. Specifically, we ask whether the phase shifts in the rhythms in axial length and choroid thickness (two ocular circadian rhythms the phases of which have been shown to be altered by visual manipulations that alter growth rate) are temporally correlated with visually induced changes in rate of ocular growth. This would imply that the changes in thickness of the choroid might play a causal role in ocular growth regulation. To further explore this notion we will test the hypothesis that daily transient changes in choroidal thickness are part of the signal pathway mediating emmetropization. Specifically, we ask whether the visual signals mediating changes in choroidal thickness and those mediating changes in ocular growth rate are the same, or are separate. Finally, we will look at some visual and chemical effects on the circadian rhythm in scleral proteoglycan synthesis to further explore how the phases of these ocular rhythms might interact in regulating ocular growth. We will also test the hypothesis that there is a diurnal rhythm in choroidal retinoic acid synthesis that might influence the diurnal rhythm in scieral proteoglycan synthesis. The results from these three Aims will bring us closer to understanding the molecular mechanisms underlying ocular growth regulation, and elucidate the influence of the choroid in these mechanisms.

描述（由申请人提供）：在美国，近视影响近25％的人口，而在某些其他发达国家中，受影响的人口比例增加到80％或更多。病理近视也是失明的主要原因。因此，了解监管眼增长的基础机制对于理解它如何以及为何在发展出抗肌瘤的眼睛中出现问题而至关重要，并可能导致新疗法的发展。 最近的工作表明，眼增长速率的变化与眼部昼夜节律的改变有关。这里提出的工作旨在扩展这些原始观察结果，以更好地了解这些效果的基础机制。具体而言，我们询问轴向长度和脉络膜厚度（两个眼昼夜节律的相位阶段）是否已通过改变生长速率的视觉操纵改变了轴向厚度的相位移位是否与视觉诱导的眼部生长速率变化相关。这意味着脉络膜厚度的变化可能在眼部生长调节中起因果作用。为了进一步探讨这一观点，我们将测试以下假设：脉络膜厚度的每日短暂变化是介导弹性化的信号途径的一部分。具体而言，我们询问视觉信号是介导脉络膜厚度变化的视觉信号以及眼部生长速率的介导变化是相同的还是分开的。最后，我们将研究对巩膜蛋白聚糖合成中昼夜节律的一些视觉和化学作用，以进一步探讨这些眼部节律的相位如何在调节眼部生长方面相互作用。我们还将检验以下假设：脉络膜视黄酸合成中存在昼夜节奏，可能会影响粘液蛋白聚糖合成中的昼夜节奏。这三个目标的结果将使我们更加接近理解眼部生长调节的分子机制，并阐明脉络膜在这些机制中的影响。