Brief light exposure at night disrupts the circadian rhythms in eye growth and choroidal thickness in chicks
Brief light exposure at night disrupts the circadian rhythms in eye growth and choroidal thickness in chicks
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DOI：
10.1016/j.exer.2016.03.003
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发表时间：
2016-05-01
影响因子：
3.4
通讯作者：
Totonelly, Kristen
中科院分区：
文献类型：
--
作者：
Nickla, Debora L.;Totonelly, Kristen
在正视化动物模型中，导致近视或远视的眼生长变化与眼生长、脉络膜厚度和眼内压的昼夜节律改变相关。最近的研究表明，夜间的光对人类健康有有害影响，通过各种昼夜节律的“昼夜节律中断”起作用，包括相位或振幅的变化。本研究的目的是要确定的影响，简短的，2小时的光在半夜的节奏轴长和脉络膜厚度，以及是否这些改变眼睛的生长和屈光不正的小鸡模型的近视眼。从2周龄开始，鸟类接受2小时的光之间的12：00和2：00上午7天（n = 12;总小时的光：14小时）。对照组有连续黑夜（n = 14; 14 L/10 D）。在实验的第一天使用高频A-扫描超声波测量眼睛尺寸，并在第7天再次以6小时间隔测量，从中午开始（12 pm，6 pm，12 am，6 am，12 pm）。夜间的测量在摄影安全灯下进行。这些数据用于确定相位和幅度的节律参数。在4周的过程中，以不同的间隔用超声波测量2组鸟，实验组（夜间光照）和对照组，以确定生长速率。实验2周后测量6只实验组和6只对照组的屈光不正，结果表明，正常L/D周期的鸟类眼轴长度和脉络膜厚度均呈正弦24 h周期性昼夜节律。半夜的光引起轴长和脉络膜厚度的节律的变化，使得两者都不能拟合具有24小时周期的正弦函数。在随后的6小时内（12 am-6 am），光引起了急性、短暂的眼生长率刺激，这可能是4周后眼生长率增加和近视屈光不正增加的原因。它也废除了脉络膜厚度的增加，通常发生在下午6点和12点之间。我们得出结论，在夜间光改变眼轴长度和脉络膜厚度的动物模型的眼睛生长的节奏，这些昼夜节律的中断可能会导致屈光不正的发展。这些结果对儿童在夜间使用灯光有影响。(c)2016爱思唯尔有限公司版权所有
Changes in ocular growth that lead to myopia or hyperopia are associated with alterations in the circadian rhythms in eye growth, choroidal thickness and intraocular pressure in animal models of emmetropization. Recent studies have shown that light at night has deleterious effects on human health, acting via "circadian disruptions" of various diurnal rhythms, including changes in phase or amplitude. The purpose of this study was to determine the effects of brief, 2-h episodes of light in the middle of the night on the rhythms in axial length and choroidal thickness, and whether these alter eye growth and refractive error in the chick model of myopia.Starting at 2 weeks of age, birds received 2 h of light between 12:00 am and 2:00 am for 7 days (n = 12; total hours of light: 14 h). Age-matched controls had a continuous dark night (n = 14; 14L/10D). Ocular dimensions were measured using high-frequency A-scan ultrasonography on the first day of the experiment, and again on day 7, at 6-h intervals, starting at noon (12 pm, 6 pm, 12 am, 6 am, 12 pm). Measurements during the night were done under a photographic safe-light. These data were used to determine rhythm parameters of phase and amplitude. 2 groups of birds, both experimental (light at night) and control, were measured with ultrasound at various intervals over the course of 4 weeks to determine growth rates. Refractive errors were measured in 6 experimental and 6 control birds at the end of 2 weeks.Eyes of birds in a normal L/D cycle showed sinusoidal 24-h period diurnal rhythms in axial length and choroid thickness. Light in the middle of the night caused changes in both the rhythms in axial length and choroidal thickness, such that neither could be fit to a sine function having a period of 24 h. Light caused an acute, transient stimulation in ocular growth rate in the subsequent 6-h period (12 am-6 am), that may be responsible for the increased growth rate seen 4 weeks later, and the more myopic refractive error. It also abolished the increase in choroidal thickness that normally occurs between 6 pm and 12 am.We conclude that light at night alters the rhythms in axial length and choroidal thickness in an animal model of eye growth, and that these circadian disruptions might lead to the development of ametropias. These results have implications for the use of light during the night in children. (c) 2016 Elsevier Ltd. All rights reserved.