摘要
目的探讨准分子激光术后大鼠角膜中Ⅰ型前胶原的变化,比较角膜非手术区、手术野透明区与上皮下雾状混浊(haze)区的Ⅰ型前胶原含量的差异。方法 32只6月龄清洁级SD大鼠按照手术前后被处死的时间不同平均分为8组。28只大鼠的一侧眼被施行准分子激光角膜切削术(PRK)。术后每日裂隙灯显微镜下观察术眼角膜情况,角膜haze的分级参照Seiler标准。分别于手术前和术后1、3、7、15d及1、2、3个月处死动物,行苏木精-伊红染色,观察手术区角膜的形态变化,采用免疫组织化学法检测角膜Ⅰ型前胶原在术眼角膜组织中的表达,并以光密度(OD)值表示。对不同时间采集的角膜非手术区、手术野透明区与haze区中Ⅰ型前胶原含量进行定量分析。结果自术后3d起,术眼角膜上皮开始移行覆盖切削区并逐渐增厚,基质纤维细胞增生活跃;术后1个月时术眼角膜上皮基底膜开始形成,基质胶原纤维排列紊乱;术后3个月角膜基质胶原重塑过程基本完成,角膜结构趋于正常。大鼠角膜术后haze分级与Ⅰ型前胶原含量呈正相关(r=0.406,P<0.05);非手术区各时间段角膜平均OD值均无明显变化(t=5.719,P>0.05);手术区角膜中的Ⅰ型前胶原含量明显高于非手术区(P<0.05);haze区平均OD值明显高于非haze区(t=5.578,P<0.05)。免疫组织化学检测表明,角膜上皮中Ⅰ型前胶原的阳性表达在术后7d最多,并终止于术后1个月,而角膜细胞间质中Ⅰ型前胶原持续至整个修复过程。结论Ⅰ型前胶原含量的增加可能是haze形成的主要因素之一,为进一步研究准分子激光术后角膜前胶原的变化提供理论支持。
Background Some researches indicated that formation of cornea haze after excimer laser keratorefractive surgery may he associated with the abnormality of corneal collagen tissue. Human corneal stroma primarily consists of collagen type I. Objective This study was to explore the changes of corneal precollagen type I following the photorefractive keratectomy （PRK） and compare the difference of precollagen type Ⅰ content between non-operation area, transparent cornea area and haze area. Methods Thirty-two 6-month-old clean SD rats were divided into 8 groups and 4 for each according to the sacrificed time points. PRK models were established in 28 SD rats. Haze formation of cornea＇was examined under the slim-lamp microscope once a day after surgery and graded based on the criteria of Seiler. The rats were sacrificed before surgery, 1 ,3,7,15 days,1,2,3 months after surgery respectively and the cornea samples were obtained. Precollagen type Ⅰ in cornea was detected and quantitatively analyzed by immunochemistry. The use of the animals followed the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission. Results Corneal epithelial cells moved toward and covered the operation zone in postoperative day 3 and stratified in the sequentia period. Basement membrane of corneal epithelium formed until 1 month after PRK procedure,however,there still existed chaos of collagen in arrangement. After surgery, the graduation of haze was obviously correlated with the content of precollagen type Ⅰ （ r = 0. 406, P 〈 0.05）. After PRK procedure,the content of corneal precollagen type Ⅰ elevated gradually along with the time expanded and peaked two months later. The level of preeollagen type Ⅰ in the transparent cornea zone was higher than the non-operation zone obviously（ t = 5. 719, P〈0.05）,and that in the haze area was higher than the non-haze area obviously（t =5.578,P 〈0.05）. The H＆E staining revealed that the basement membrane appeared
出处
《眼科研究》
CSCD
北大核心
2010年第5期436-440,共5页
Chinese Ophthalmic Research
基金
衡阳市2009年社会发展科技支撑项目(2009ks38)
