title: Hypergravity Effects on the Retina and Intraocular Pressure in Mice.
abstract: BACKGROUND
  We investigated the effect of exposure to +10.0 G for 4 h on the intraocular pressure and the retina of mice.
  
  
  METHODS
  We exposed 10 mice to +10.0 Gz for 4 h by using a centrifugal acceleration test facility for animals. Intraocular changes were compared before and after hypergravity exposure. The eyeballs of the mice were enucleated after measuring the intraocular pressure. Tissue slides of the retina were prepared with hematoxylin and eosin (H&E) for histological examination and immunohistochemical analyses for vascular endothelial growth factor-A (VEGF-A), VEGF receptor 1 (VEGF-R1), VEGF-R2, glial fibrillary acidic protein (GFAP), and glutamine synthetase (GS).
  
  
  RESULTS
  The average intraocular pressure was 7.7 ± 0.86 mmHg before the hypergravity exposure and 6.65 ± 0.67 mmHg after the exposure. No histological difference was observed between the retinas in the two groups. The levels of VEGF-A, VEGF-R1, VEGF-R2, GFAP, and GS as assessed by immunohistochemistry were increased in the group exposed to hypergravity compared to the control group.
  
  
  CONCLUSIONS
  Repeated exposure to a high level of hypergravity could cause elevation of intraocular pressure and hypoxic damage to the retina.
authors.affiliation: Department of Ophthalmology, Inha University College of Medicine, Incheon, Republic of Korea.
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Kim
authors.forename: Jae Seung
authors.initials: JS
authors.lastname: Chung
authors.forename: Tae Young
authors.initials: TY
authors.lastname: Jang
authors.forename: Young Hyo
authors.initials: YH
authors.lastname: Kim
authors.forename: Hee Seung
authors.initials: HS
authors.lastname: Chin
mesh_terms: D000818:Animals; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005974:Glutamate-Ammonia Ligase / Q000378:metabolism; D018471:Hypergravity; D007150:Immunohistochemistry; D007429:Intraocular Pressure / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D040262:Receptors, Vascular Endothelial Growth Factor / Q000378:metabolism; D012160:Retina / Q000378:metabolism / Q000502:physiology*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D005904:Glial Fibrillary Acidic Protein; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; D040262:Receptors, Vascular Endothelial Growth Factor; D005974:Glutamate-Ammonia Ligase