REDUCED EXTRACELLULAR-MATRIX IN MAMMALIAN SCLERA WITH INDUCED MYOPIA
REDUCED EXTRACELLULAR-MATRIX IN MAMMALIAN SCLERA WITH INDUCED MYOPIA
复制标题
DOI：
10.1016/0042-6989(94)00243-f
复制
发表时间：
1995-05-01
期刊：
影响因子：
1.8
通讯作者：
RADA, JA
中科院分区：
文献类型：
--
作者：
NORTON, TT;RADA, JA
本研究的目的是了解是否视觉形觉剥夺，导致近视眼，改变了树，一种哺乳动物密切相关的灵长类动物的巩膜细胞外基质。用半透明漫射器对10只树鼩进行单眼剥夺，诱导其轴性近视。每只动物的另一只眼睛是未处理的对照。剥夺21天后，测量屈光状态和轴向分量尺寸，并测定巩膜和角膜样品中DNA、羟脯氨酸和硫酸化糖胺聚糖（GAG）的水平。与开放的对照眼相比，剥夺的眼睛变得近视和细长。在巩膜中，DNA水平与对照眼相比没有显著变化。与对照眼相比，剥夺眼的后极（-15.6%）、鼻赤道区（-18.1%）和其余巩膜（-11.6%）硫酸化GAG水平显著较低。羟脯氨酸水平仅在后极显著较低（-11.8%）。相对于DNA和相对于总巩膜中的羟脯氨酸，硫酸化GAG的水平显著降低。角膜未见明显变化。与对照眼相比，剥夺眼的整个巩膜中硫酸化GAG的水平较低，表明剥夺的巩膜含有较少的蛋白聚糖，或者蛋白聚糖较少糖基化或较少硫酸化。相反，羟脯氨酸的区域减少表明，胶原蛋白的积累是专门减少，只有在后极的剥夺眼睛。这些结果表明，形觉剥夺减缓或逆转了这种哺乳动物巩膜中细胞外基质积累的正常过程。这可能允许巩膜更扩张，允许玻璃体腔延长和由此产生的近视。
The purpose of this study was to learn whether visual form deprivation, which produces myopia in the deprived eye, alters the scleral extracellular matrix in tree shrew, a mammal closely related to primates. Axial myopia was induced in 10 tree shrews by monocular deprivation imposed with a translucent diffuser. The other eye in each animal was an untreated control. After 21 days of deprivation the refractive state and axial component dimensions were measured and the eyes were assayed for levels of DNA, hydroxyproline, and sulfated glycosaminoglycans (GAGs) in samples of the sclera and the cornea. In comparison to the open control eye, the deprived eyes became myopic and elongated. In the sclera, DNA levels were not significantly changed from the control eye. Sulfated GAG levels were significantly lower in the deprived eyes, as compared to the control eyes, at the posterior pole (-15.6%), at the nasal equatorial region (-18.1%), and in the rest of the sclera (-11.6%). The hydroxyproline level was significantly lower only at the posterior pole (-11.8%). Levels of sulfated GAGs were significantly reduced relative to DNA and relative to hydroxyproline in the total sclera. No significant changes were found in the cornea. The lower level of sulfated GAGs throughout the sclera of the deprived eyes, as compared with the control eyes, suggests that the deprived sclera contained less proteoglycan, or that the proteoglycans were less glycosylated or less sulfated. In contrast, the regional reduction of hydroxyproline suggests that collagen accumulation was specifically reduced only at the posterior pole of deprived eyes. These results suggest that form deprivation slows or reverses the normal process of extracellular matrix accumulation in the sclera of this mammal. This may allow the sclera to be more distensible, permitting the vitreous chamber elongation and resultant myopia.