title: Proliferation of the vascular endothelium of the iris following total debridement of the corneal epithelium and limbal excision of rabbits.
abstract: BACKGROUND
  Damage to the corneal epithelium causes not only a reaction for its repair but also affects other parts of the cornea as well as different components of the anterior segment of the eye. The purpose of this investigation was to analyze the consequences, following epithelial and limbal damage, to the iris of rabbits (Oryctolagus cuniculus).
  
  
  METHODS
  The corneal epithelium was thoroughly scraped followed by surgical excision of the limbus. Next, (3)H-thymidine ((3)H-TdR) was injected intravitreally both into the right (experimental) and left (control) eyes which had their anterior segments processed for autoradiography at intervals of 2, 7 and 21 days after surgery (three rabbits per interval). The irises were also examined with scanning-electron and confocal microscopy after Evans blue injection.
  
  
  RESULTS
  There was a high frequency of labeling in the cells of the iris blood vessels in the experimental eye, particularly the endothelial ones. The ratio of labeled cells between experimental and control irises was 40:1, with a population of nuclei increasing by 25% and remaining labeled up to 21 days. There was also an increase in the volume of the iris vasculature as shown by confocal microscopy. The high labeling frequencies of the vascular cells were observed throughout the iris from the ciliary to the pupillary regions.
  
  
  CONCLUSIONS
  The lesions on the corneal epithelium elicit proliferation of the iris vascular cells, mainly its endothelium, as well as an early breakdown of the blood-aqueous barrier. The daughter cells resulting from the damage to the eye surface were detected up to 21 days after a single injection of (3)H-TdR, most likely due to their slow turnover. As a consequence of this proliferation, the vasculature of the iris increased in volume.
authors.affiliation: Departamento de Biologia, São Paulo State University - IBILCE - UNESP, Faculdade de Medicina de Ribeirão Preto/USP, Ribeirão Preto, SP, Brasil.
authors.forename: Rejane Maira
authors.initials: RM
authors.lastname: Góes
authors.forename: Flávia Leão
authors.initials: FL
authors.lastname: Barbosa
authors.forename: Sidney Júlio
authors.initials: SJ
authors.lastname: de Faria-E-Sousa
authors.forename: João Kazuyuki
authors.initials: JK
authors.lastname: Kajiwara
authors.forename: Antonio
authors.initials: A
authors.lastname: Haddad
mesh_terms: D000818:Animals; D001345:Autoradiography; D018916:Blood-Aqueous Barrier; D002452:Cell Count; D049109:Cell Proliferation; D003646:Debridement; D004730:Endothelium, Vascular / Q000473:pathology*; D019573:Epithelium, Corneal / Q000601:surgery*; D007498:Iris / Q000098:blood supply* / Q000648:ultrastructure; D016850:Limbus Corneae / Q000601:surgery*; D008297:Male; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D011817:Rabbits; D014945:Wound Healing