Effects of endothelin-1 and mitomycin C on rabbit corneas after photorefractive keratectomy

• Main Authors: Yu-Hung Lai, MD, 賴昱宏
• Other Authors: Hwei-Zu Wang, MD.
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/57348226413698358462

碩士 === 高雄醫學大學 === 醫學研究所 === 91 === Purpose We studied the effects of endothelin-1 (ET1) and mitomycin C (MMC) on rabbit corneas after photorefractive keratectomy (PRK). Materials and Methods Sixty-six male New Zealand white rabbits were included in the study. There were 33 rabbits in the ET1 group, and 33 in the MMC group. ET1 group: After PRK, ET1 was applied to the right eye and phosphate-buffered salt solution (PBS) to the left five time a day for seven days. We recorded size of corneal epithelial wound and grade of corneal haze. Ultrasound pachymeter was used to measure the thickness of the rabbit corneas. The apoptosis of keratocytes was evaluated by TUNEL assay and transmission electron microscope (TEM). The extracellular matrix of the corneas was studied by using immunohistochemistry. MMC group: Dichlorotriazinyl aminofluorescein (DTAF) was applied to the wound immediately after PRK. MMC was applied to the right eye and PBS to the left twice daily for five days. We recorded size of corneal epithelial wound and grade of corneal haze. Ultrasound pachymeter was used to measure the thickness of the rabbit corneas. The thickness of the new-formed collagen after laser treatment was measured by fluorescent microscopy. The apoptosis of keratocytes was evaluated by TUNEL assay and TEM. Results ET1 promoted the healing of the corneal epithelial wound in rabbit corneas. The duration of keratocyte apoptosis was prolonged in the eyes treated by ET1. There was no significant difference in corneal haze, changes of corneal thickness, or in extracellular matrix between right and left eyes. MMC did not delay the healing rate of the corneal epithelial wound. The duration of keratocyte apoptosis was prolonged in the eyes treated by MMC. MMC inhibited cornea thickening and new collagen formation. MMC improved the haze earlier than the control after PRK. Conclusion ET1 promoted corneal epithelial wound healing. MMC improved corneal haze, decreased cornea thickening, and inhibited new collagen formation in corneal stroma without delaying the healing of corneal epithelium. The two medications are potential drugs for wound modulation.