Glycosaminoglycan synthesis in the separate layers of the chick sclera during myopic eye growth: Comparison with mammals
Glycosaminoglycan synthesis in the separate layers of the chick sclera during myopic eye growth: Comparison with mammals
复制标题
DOI：
10.1076/ceyr.23.3.179.5466
复制
发表时间：
2001-09-01
影响因子：
2
通讯作者：
McBrien, NA
中科院分区：
文献类型：
--
作者：
Gentle, A;Truong, HT;McBrien, NA
目的.在屈光发展的动物模型中的研究表明，诱导性近视的发展和恢复与巩膜糖胺聚糖合成的视觉引导变化相关。本研究试图确定是否存在差异模式的巩膜糖胺聚糖合成的纤维巩膜层的小鸡在近视的发展或恢复，如先前已报道的哺乳动物sclera. Methods。通过单眼剥夺模式视觉5天以上，在幼鸡中诱导近视。其他动物进行单眼剥夺，然后取出封堵器，并允许恢复2天。一组年龄匹配的正常动物作为对照。在巩膜层中新合成的糖胺聚糖在体内标记，使用[S-35]-标记的前体在最后实验日腹膜内递送。通过用阿辛蓝选择性沉淀，在蛋白酶K酶中评估这种硫酸盐与纤维和软骨巩膜层的糖胺聚糖的结合。近视眼和恢复眼的纤维巩膜层中的糖胺聚糖合成与对侧对照眼无显著差异（分别为+14 +/-7%，p = 0.09和-2 +/-4%，p = 0.64）。相比之下，与对照组相比，近视眼巩膜软骨层糖胺聚糖的合成显著增加（+63 +/-18%，p < 0.02），而恢复期眼软骨层糖胺聚糖的合成显著减少（-40 +/-6%，p < 0.001）。本研究的结果表明，小鸡的纤维巩膜层不显示在近视发展和恢复期间在哺乳动物巩膜中发现的糖胺聚糖合成的特征性差异模式。然而，如先前所报道的，鸡巩膜的软骨层确实显示出不同的糖胺聚糖表达，尽管调节方向与哺乳动物纤维巩膜中发现的相反。
Purpose. Studies in animal models of refractive development have shown that the development of and recovery from induced myopia is associated with visually-guided changes in scleral glycosaminoglycan synthesis. The present study sought to determine whether differential patterns of scleral glycosaminoglycan synthesis are present in the fibrous scleral layer of the chick during myopia development or recovery, as has previously been reported in the mammalian sclera.Methods. Myopia was induced in young chicks by monocular deprivation of pattern vision over 5 days. Other animals underwent monocular deprivation, then had the occluder removed and were allowed 2 days of recovery. A group of age-matched normal animals served as a control. Newly synthesised glycosaminoglycans in the scleral layers were labelled in vivo, using a [S-35]-labelled precursor delivered intraperitoneally on the final experimental day. Incorporation of this sulphate into glycosaminoglycans of the fibrous and cartilaginous scleral layers was assessed in proteinase K digests by selective precipitation with alcian blue.Results. Glycosaminoglycan synthesis in the fibrous scleral layers of myopic and recovering eyes was not significantly different to contralateral control eyes (+14 +/- 7%, p = 0.09 and -2 +/- 4%, p = 0.64 respectively). In contrast, glycosaminoglycan synthesis was significantly elevated, relative to controls, in the cartilaginous scleral layer of eyes developing myopia (+63 +/- 18%, p < 0.02), whereas in recovering eyes there was found to be a significant decrease in synthesis in the cartilaginous layer (-40 +/- 6%, p < 0.001).Conclusions. The results of the current study demonstrate that the fibrous scleral layer of the chick does not display the characteristic differential patterns of glycosaminoglycan synthesis that are found in the mammalian sclera during myopia development and recovery. However, as has previously been reported, the cartilaginous layer of the chick sclera does display differential glycosaminoglycan expression, although the direction of regulation is opposite to that found in the fibrous sclera of mammals.