负透镜诱导豚鼠离焦性近视眼巩膜胶原密度及形态学改变

目的探讨新生豚鼠负透镜诱导离焦性近视发生时巩膜胶原密度和形态的变化。方法30只新生有色豚鼠随机分成透镜诱导组（单眼-10.00D透镜诱导）和正常对照组（无处理组）,第28天测量屈光度,眼球冰冻切片行VanGieson胶原染色,以锯齿缘为界分别分析前后部巩膜胶原密度;并进行电镜扫描观察巩膜胶原纤维直径。结果新生豚鼠28d透镜诱导组诱导眼的平均球镜等值屈光度低于对侧眼（P〈0.01）;诱导眼后部巩膜胶原染色光密度值低于对侧眼（P〈0.01）;诱导眼和对侧眼屈光度差值与后部巩膜胶原染色光密度差值呈正相关（r=0.84,P〈0.01）;诱导眼后部巩膜胶原纤维直径小于对侧眼（P〈0.01）;诱导眼前部巩膜胶原密度和胶原直径与对侧眼相比,差异无统计学意义（P〉0.05）;新生豚鼠28d诱导组对侧眼各项指标与对照组相比,差异无统计学意义（P〉0.05）。结论新生豚鼠负透镜诱导离焦性近视时后部巩膜胶原密度减少,伴胶原直径的减小,影响胶原代谢的机制尚需进一步研究。

Collagen density and morphologic change of sclera in guinea pigs with negative lens-defocused myopia

Objective The development of the eye refractive state could be manipulated with spectacle lenses, and it is commonly associated with the changes in collagen structure of selera. The aim of present work was to investigate whether defocus through negative lens alters the density and morphology of selera collagen in guinea pigs. Methods The negative lens- defoeused myopia was induced by monocularly defocusing by-10 D lens in the right eyes of 20 newborn guinea pigs weighted 70 - 90 grams. The fellow eyes of the guinea pigs were as self-control. Other 10 normal guinea pigs were as normal control. After 28 days of defocusing,the diopter was examined by retinoscopy. Ten model eyes and 5 normal eyeballs were enucleated and the seleral sample was dissected for Van Gieson staining and transmission electronic microscopy examination. Results On the 28 days,the mean diopter value was（ - 1.28±0. 39） D,showing a significant change in comparison with the fellow eyes（ ＋4.67 ± 1.01 ） （P 〈 0.05 ） , and the considerably difference was found in mean difference value of both eyes between lens-defocused group and normal control group（ P 〈 0.05 ）. The collagen density of sclera at the posterior region of model eyes were significantly lower, and the collagen fibrillar diameter was significantly thinner in posterior sclera in the model eyes compared with fellow eyes （P 〈 0.01 ）. The positive correlation was revealed between refractive status and collagen density （ r = 0.84, P 〈 0. 01 ）. However, no significant difference was found in the density and fibrillar diameter of anterior sclera in the model eyes compared with fellow eyes （P 〉 0.05 ）, and no significant difference was revealed in refractive status, collagen density fibrillar diameter in fellow eyes compared with normal control eyes（ P 〉 0. 05 ）. The collagen staining was weaker in model eyes than the fellow eyes and normal eyes. The collagen fibers were thinner and presented the irregular arrangement in the model eye under the trans