The effect of raised inspired carbon dioxide on normal retinal vascular development in the neonatal rat

Curr Eye Res. 1997 Jan;16(1):78-81. doi: 10.1076/ceyr.


Purpose: Raised arterial carbon dioxide levels have been suggested as a risk factor for retinopathy of prematurity (ROP). We investigated the effect of raised inspired CO2 on normal postnatal vasculogenesis in the neonatal rat retina.

Methods: One hundred fifty newborn rat pups were divided among 15 mothers (n = 10 for each litter). Five litters were exposed to low CO2 (0.2%), 5 litters exposed to 6%, and 5 litters to 10% CO2. On day 7 of life the rats were sacrificed and the total retinal and vascularized retinal areas analyzed.

Results: The vascularized retinal area and ratio of vascularized to total retinal area were reduced in rats exposed to 6% and 10% CO2.

Conclusions: Raised inspired CO2 was associated with retardation of normal retinal vascular development and increased peripheral avascular area in neonatal rats. Raised CO2 may be a risk factor for the development of abnormal neovascularization such as in ROP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Carbon Dioxide / administration & dosage
  • Fluorescein Angiography
  • Fundus Oculi
  • Humans
  • Hypercapnia / physiopathology*
  • Infant, Newborn
  • Random Allocation
  • Rats
  • Rats, Sprague-Dawley
  • Respiration
  • Retinal Neovascularization / pathology
  • Retinal Neovascularization / physiopathology*
  • Retinal Vessels / growth & development
  • Retinal Vessels / pathology*
  • Retinal Vessels / physiopathology
  • Retinopathy of Prematurity / pathology
  • Retinopathy of Prematurity / physiopathology


  • Carbon Dioxide