title: Morphological and morphometric changes in rat optic nerve microvessels in a glaucoma experimental model.
abstract: OBJECTIVE
  To study the morphological and morphometric changes produced in the capillaries of the optic nerve (ON) head and initial portion after the experimental increase in intraocular pressure (IOP).
  
  
  METHODS
  Wistar rats underwent cauterization of three episcleral veins, which produced an immediate increase in the IOP, and was maintained for 3 months. Sagittal sections of the eyeball were studied with immunohistochemical techniques, using a primary antibody to GLUT-1. The GLUT-1 positive capillaries were counted, and measurements were made of the area, perimeter and mean diameter.
  
  
  RESULTS
  Microscopic examination of sections of the ON of control rats revealed a lower density and larger caliber of capillaries in the prelaminar region as compared with the other regions of the ON (P<.05). Comparison between the control and the experimental groups showed a reduction in capillary density (except in the prelaminar region) and a smaller size in all the areas of the ON studied, but less evident in the initial portion (P<.05).
  
  
  CONCLUSIONS
  The increase in IOP was associated with significant qualitative and quantitative changes in the capillaries of the laminar and poslaminar regions of the ON head. These changes appear to return towards parameters compatible with normality in the initial portion of the ON, an area where the vascular collapse was less evident. These findings might explain the significant reduction in ocular blood flow seen in patients with primary open-angle glaucoma.
authors.affiliation: Área de Oftalmología, Facultad de Medicina, Universidad de Málaga, Málaga, España.
authors.forename: M
authors.initials: M
authors.lastname: Moreno
authors.affiliation: Área de Histología, Facultad de Medicina, Universidad de Málaga, Málaga, España.
authors.forename: M C
authors.initials: MC
authors.lastname: Ríos
authors.affiliation: Área de Histología, Facultad de Medicina, Universidad de Málaga, Málaga, España.
authors.forename: C
authors.initials: C
authors.lastname: Alba
authors.affiliation: Área de Histología, Facultad de Medicina, Universidad de Málaga, Málaga, España.
authors.forename: F
authors.initials: F
authors.lastname: Díaz
authors.affiliation: Área de Histología, Facultad de Medicina, Universidad de Málaga, Málaga, España.
authors.forename: A
authors.initials: A
authors.lastname: Villena
authors.affiliation: Área de Oftalmol-Biología, Centro de Investigaciones Médico-Sanitarias, Universidad de Málaga, Málaga, España.
authors.forename: L C
authors.initials: LC
authors.lastname: Figueroa-Ortiz
authors.affiliation: Área de Oftalmología, Facultad de Medicina, Universidad de Málaga, Málaga, España; Área de Oftalmol-Biología, Centro de Investigaciones Médico-Sanitarias, Universidad de Málaga, Málaga, España; Servicio de Oftalmología, Hospital Virgen de la Victoria, Málaga, España. Electronic address: jmgarcia@uma.es.
authors.forename: J
authors.initials: J
authors.lastname: García-Campos
mesh_terms: D000818:Animals; D015415:Biomarkers; D002196:Capillaries / Q000648:ultrastructure*; D015687:Cell Hypoxia; D004195:Disease Models, Animal; D005901:Glaucoma / Q000473:pathology*; D051272:Glucose Transporter Type 1 / Q000032:analysis; D007429:Intraocular Pressure; D008297:Male; D017628:Microglia / Q000502:physiology; D009898:Optic Disk / Q000098:blood supply; D009900:Optic Nerve / Q000098:blood supply*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D015415:Biomarkers; D051272:Glucose Transporter Type 1
keywords: Barrera hematoencefálica; Capilares; Capillaries; GLUT-1; Hematoencephalic barrier; Intraocular pressure; Nervio óptico; Optic nerve; Presión intraocular