Texas Eye Research and Technology Center, University of Houston College of Optometry, Houston, Texas 770204-2020, USA.
Clin Exp Ophthalmol. 2012 Mar;40(2):174-81. doi: 10.1111/j.1442-9071.2011.02652.x. Epub 2011 Sep 19.
The mouse corneal stroma varies in thickness across its diameter. The purpose of the present study was to explain this variation and to advance our understanding of stromal lamellar architecture in the mammalian cornea.
Eight C57BL/6 mice were killed, eyes enucleated, immersed in 2% glutaraldehyde fixative, processed and sectioned transversely for light and transmission electron microscopy. Transmission electron micrographs were assembled into montages and printed at 5000× magnification and used for lamellar counts and thickness assessments.
The mouse cornea had an average of 49.8±2.4 lamellae centrally averaging 2.1µm in thickness versus 35.5±3.0 lamellae, averaging 1.9µm in thickness peripherally. The central to peripheral decrease in number lamellae and lamellar thickness measured utilizing the transmission electron microscope was statistically significant (P<0.005).
This study demonstrated that the thickness difference between the thicker central and thinner peripheral mouse cornea is explained primarily by the number of lamellae present and that the peripheral lamellar dropout occurred in the anterior 2/3 of stroma. The decreased lamellar count towards the periphery suggested that not all lamellae cross the cornea limbus to limbus. These findings may be relevant to the thickness variation of the human cornea.
小鼠角膜基质在其直径上的厚度存在差异。本研究旨在解释这种变化，并深入了解哺乳动物角膜基质的板层结构。
8 只 C57BL/6 小鼠被处死，眼球被取出，浸泡在 2%戊二醛固定液中，进行处理并横向切片，用于光镜和透射电镜检查。透射电镜照片被组装成拼贴画，并以 5000×的放大倍数打印出来，用于板层计数和厚度评估。
小鼠角膜中央平均有 49.8±2.4 个板层，厚度为 2.1µm，而周边平均有 35.5±3.0 个板层，厚度为 1.9µm。利用透射电镜测量的中央到周边板层数量和板层厚度的减少具有统计学意义（P<0.005）。
本研究表明，较厚的中央和较薄的周边小鼠角膜之间的厚度差异主要由存在的板层数解释，并且周边板层缺失发生在前部 2/3 的基质中。周边板层数量的减少表明并非所有板层都穿过角膜缘到角膜缘。这些发现可能与人类角膜的厚度变化有关。
