Henan Eye Institute, Henan Eye Hospital, Department of Ophthalmology, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Zhengzhou 450003, People's Republic of China.
Exp Eye Res. 2013 Oct;115:255-62. doi: 10.1016/j.exer.2013.07.025. Epub 2013 Aug 3.
The mouse corneal thickness is very important for research into the fields of eye disease. However, the in vivo corneal thickness for the entire cornea from the pupil to the limbus was not determined. We measured in vivo corneal layer thicknesses in different corneal areas, from the central cornea to the limbus, in the widely used inbred C57BL/6 and BALB/c mouse strains using two-photon (2 PH) imaging. Eight corneas of the C57BL/6 or BALB/c were scanned using a 2 PH laser scanning fluorescence microscopy system. A total of 14 thicknesses of the different corneal layers, from different corneal regions, were measured using image processing software. In both C57BL/6 and BALB/c mice, the thickness of the corneal layers was inhomogeneous in different areas of the cornea, and all of the layers had their minimum thickness at the limbus. In C57BL/6 mice, the thickness of the corneal layers gradually increased from the central to the paracentral cornea, peaked at the fifth measurement point in the paracentral area, and decreased from this point to the limbus. In BALB/c mice, the thickness of the entire cornea and corneal epithelium had its maximum at the central cornea and gradually decreased from the central cornea to the peripheral cornea and to the limbus. The thickness of the corneal stroma and endothelium had its maximum at the fourth measurement point in the paracentral cornea and gradually decreased from the paracentral cornea to the limbus. The ratio of epithelial thickness to the total corneal thickness gradually decreased from the central cornea to the limbus in both C57BL/6 and BALB/c mice. The minimum ratio was observed at the fourteenth measurement point in both C57BL/6 and BALB/c mice. The ratio of stromal and endothelial to the total corneal thickness gradually increased from the central cornea to the limbus in both C57BL/6 and BALB/c mice. The maximum ratio was observed at the fourteenth measurement point in C57BL/6 mice. The ratio at the first eight measurement points was significantly lower in BALB/c than in C57BL/6 mice (P < 0.05). Our study demonstrated that the thickness of the entire cornea, the corneal epithelium, the corneal stroma and the endothelium was inhomogeneous in different areas of the cornea. Moreover, all of the layers exhibited a minimum thickness at the limbus in both C57BL/6 and BALB/c mice. Furthermore, the corneal thickness in different areas varied between C57BL/6 and BALB/c mice, and the variation in thickness with respect to corneal location for these strains was dissimilar. When using the mouse as an animal model to examine the cornea, it is important to note the differences between humans and mice.
鼠标角膜厚度对于眼部疾病领域的研究非常重要。然而，整个角膜从瞳孔到角膜缘的活体角膜厚度尚未确定。我们使用双光子（2 PH）成像技术，在广泛使用的近交系 C57BL/6 和 BALB/c 小鼠中，从中央角膜到角膜缘，测量不同角膜区域的活体角膜层厚度。使用 2 PH 激光扫描荧光显微镜系统扫描了 8 只 C57BL/6 或 BALB/c 的角膜。使用图像处理软件测量了来自不同角膜区域的不同角膜层的总共 14 个厚度。在 C57BL/6 和 BALB/c 小鼠中，角膜各层的厚度在角膜的不同区域不均匀，所有层在角膜缘处的厚度最小。在 C57BL/6 小鼠中，角膜层的厚度从中央向旁中央角膜逐渐增加，在旁中央区域的第五个测量点达到峰值，然后从该点向角膜缘减少。在 BALB/c 小鼠中，整个角膜和角膜上皮的厚度在中央角膜处最大，然后从中央角膜向周边角膜和角膜缘逐渐减少。角膜基质和内皮的厚度在旁中央角膜的第四个测量点达到最大值，然后从旁中央角膜向角膜缘逐渐减少。上皮厚度与总角膜厚度的比值在 C57BL/6 和 BALB/c 小鼠中均从中央角膜向角膜缘逐渐减小。在 C57BL/6 和 BALB/c 小鼠中，在第十四次测量点观察到最小的比值。基质和内皮与总角膜厚度的比值在 C57BL/6 和 BALB/c 小鼠中均从中央角膜向角膜缘逐渐增加。在 C57BL/6 小鼠中，在第十四次测量点观察到最大的比值。在 BALB/c 小鼠中，前八个测量点的比值明显低于 C57BL/6 小鼠（P<0.05）。我们的研究表明，整个角膜、角膜上皮、角膜基质和内皮在角膜的不同区域厚度不均匀。此外，在 C57BL/6 和 BALB/c 小鼠中，所有层在角膜缘处的厚度最小。此外，不同区域的角膜厚度在 C57BL/6 和 BALB/c 小鼠之间存在差异，并且这些品系的角膜位置与厚度之间的变化不同。当使用小鼠作为动物模型来检查角膜时，重要的是要注意人与小鼠之间的差异。
