透镜诱导性近视豚鼠生物参数及巩膜胶原含量的改变

目的探讨生物参数和巩膜胶原在透镜诱导性近视（LIM）发生发展过程中的变化及其机制。方法实验研究。选取3周龄英国种雄性三色短毛豚鼠36只，随机分为透镜诱导组（24只）和空白组（12只）。透镜诱导组右眼戴-10 D透镜诱导4周后进行检影验光和眼轴测量，并检测后极部和前部/赤道部巩膜干重、厚度，盐酸水解后检测2组相同面积后极部巩膜水解液中羟脯氨酸及氨基酸总量的改变。数据采用t检验分析。结果透镜诱导4周后豚鼠模型眼与对侧眼相比发生轴性近视（t=-14.90，P<0.01），并伴有眼轴的明显延长（t=14.76，P<0.01），差异有统计学意义，后极部巩膜干重和巩膜厚度较空白组均有明显降低（t=3.98、6.67，P＜0.01），同时后极部氨基酸总量呈下调趋势（t=3.29，P＜0.01）。结论透镜诱导可以引起豚鼠玻璃体腔的延长、后极部巩膜干重减轻、厚度变薄、胶原合成减少等一系列改变，减弱了巩膜的抵抗力，使眼轴易于延展而发生近视。

Changes in biological parameters and scleral collagen content in guinea pigs with lens-inducedmyopia

Objective To study the changes in scleral collagen and the role of these changes in the development of lens-induced myopia （LIM）. Methods Experimental study. Thirty-six three-week-old male pigmented guinea pigs were randomly assigned to the lens-induced group （n=24） and the normal control group （n=12）. The lens-induced guinea pigs were fitted with a -10 D lens on the right eye. After 4 weeks of lens wear, refractive state, axial length, dry weight and thickness of the posterior sclera and front/equator sclera, and the concentration of hydroxyproline and amino acid in the same area of the posterior sclera after hydrochloric acid hydrolysis were measured in both groups. Data were analyzed using t test. Results Axial myopia was successfully induced in the lens-induced guinea pigs after 4 weeks （t=-14.90, P〈0.01）. Axial length was longer in the LIM eyes compared with the control eyes （t=14.76, P〈0.01） and the dry weight and thickness of the posterior sclera of the LIM eyes decreased （t-~3.98, 6.67, P〈0.01）. Amino acid were also lower （t=3.29, P〈0.01）. Conclusion The lens-induced myopic eye has an elongated axial length, a thinner posterior sclera with decreased dry weight and collagen synthesis. These factors reduce the load-bearing capacity of the sclera and induce the eye to change shape.