title: [mRNA expression of transforming growth factor-beta 1 in the cornea after photorefractive keratectomy in rabbits].
abstract: OBJECTIVE
  To investigate the roles of transforming growth factor beta 1 (TGF-beta 1) during healing after photorefractive keratectomy (PRK).
  
  
  METHODS
  Twenty of 24 rabbits underwent bilateral 193 nm excimer laser photorefractive keratectomy to correct 10 diopters of myopia, and the other 4 rabbits were taken as the normal group. The mRNA levels of TGF-beta 1 in the corneas of the rabbits were determined by in situ hybridization with a Digoxigenin labled probe.
  
  
  RESULTS
  1. Corneal haze appeared in operated eyes from the 7th day, and peaked on the 28th day after PRK. The most severe haze reached Grade 3. 2. In the normal group, a low level of mRNA expression of TGF-beta 1 was observed in the epithelium, and no positive result in the stroma. On the 7th, 14th, and 28th days after the operation, the mRNA levels of TGF-beta 1 in the epithelium and stroma of the operation group were significantly higher than those in the normal group.
  
  
  CONCLUSIONS
  TGF-beta 1 may involve in corneal wound healing after PRK and may increase haze by promoting the synthesis of the extracellular matrix and the proliferation of keratocytes.
authors.affiliation: Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Hui-zhuo
authors.initials: HZ
authors.lastname: Xu
authors.forename: Shuang-zhen
authors.initials: SZ
authors.lastname: Liu
authors.forename: Xiao-bo
authors.initials: XB
authors.lastname: Xia
mesh_terms: D000818:Animals; D003315:Cornea / Q000378:metabolism* / Q000601:surgery; D003318:Corneal Opacity / Q000209:etiology / Q000378:metabolism*; D005260:Female; D054018:Lasers, Excimer; D008297:Male; D018903:Photorefractive Keratectomy / Q000009:adverse effects*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011817:Rabbits; D016212:Transforming Growth Factor beta / Q000096:biosynthesis* / Q000235:genetics; D053773:Transforming Growth Factor beta1
chemical_list: D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1