Ladage Patrick M, Yamamoto Kazuaki, Ren David H, Jester James V, Petroll W Matthew, Bergmanson Jan P G, Cavanagh H Dwight
Department of Opthalmology, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75039-9057, USA.
Eye Contact Lens. 2003 Apr;29(2):61-4. doi: 10.1097/01.ICL.0000060781.84166.80.
To determine recovery time needed for the corneal epithelium to return to a normal proliferation rate following 24-hour rigid gas-permeable (RGP) lens wear.
An RGP lens (Dk/t = 10) was fitted at 9:00 am on one randomly chosen eye of each rabbit (N = 16) and removed 24 hours later while the other eye served as a control. Following contact lens removal, the rabbits were injected at four different time intervals (1,2, 4, and 7 days) with 5-bromo-deoxyuridine (BrdU) at 9:00 am to label dividing corneal epithelial cells. All animals were sacrificed 24 hours after BrdU injection, and corneas were stained for BrdU. A series of continuously adjacent digital images of the whole-mount epithelium was collected from superior limbus to central cornea, and all BrdU-labeled epithelial cell pairs on each digitized image were counted.
On day 1 following lens removal, the number of BrdU-labeled corneal epithelium cells was reduced by 50% centrally (C) and 36% peripherally (P) (P < 0.001) compared with control eyes. At day 2, there was no statistically significant difference between control and experimental corneas (P = 0.675). At day 4, a marked significant increase in BrdU-labeled cells was noted, averaging 83% (C) and 96% (P) (P < 0.001). At day 7, BrdU-labeling returned to control values, although it was still slightly elevated (14% [C] and 5% [P], P = 0.045).
The corneal epithelium in the rabbit required at least 1 full week to recover to its stable baseline proliferation rate following only 24 hours of RGP lens wear. Interestingly, hyperproliferation was noted within the limbal, peripheral, and mid-peripheral corneal epithelium 4 days after lens removal.
确定在佩戴24小时硬性透气性（RGP）隐形眼镜后，角膜上皮恢复到正常增殖速率所需的恢复时间。
在上午9:00给每只兔子（N = 16）一只随机选择的眼睛佩戴一枚RGP隐形眼镜（Dk/t = 10），24小时后取下，另一只眼睛作为对照。取下隐形眼镜后，在四个不同时间间隔（1天、2天、4天和7天）的上午9:00给兔子注射5-溴脱氧尿苷（BrdU），以标记正在分裂的角膜上皮细胞。在注射BrdU 24小时后处死所有动物，对角膜进行BrdU染色。从角膜缘上部到角膜中央收集一系列连续相邻的全层上皮数字图像，并对每个数字化图像上所有BrdU标记的上皮细胞对进行计数。
取下隐形眼镜后的第1天，与对照眼相比，中央（C）BrdU标记的角膜上皮细胞数量减少了50%，周边（P）减少了36%（P < 0.001）。在第2天，对照角膜和实验角膜之间无统计学显著差异（P = 0.675）。在第4天，观察到BrdU标记细胞显著增加，平均增加83%（C）和96%（P）（P < 0.001）。在第7天，BrdU标记恢复到对照值，尽管仍略有升高（14% [C] 和5% [P]，P = 0.045）。
兔子的角膜上皮在仅佩戴24小时RGP隐形眼镜后，至少需要整整一周时间才能恢复到稳定的基线增殖速率。有趣的是，在取下隐形眼镜4天后，在角膜缘、周边和中周边角膜上皮内观察到增殖亢进。
