title: Local neuroretinal function during acute hypoxia in healthy older people.
abstract: OBJECTIVE
  To measure the effect of acute, mild, systemic hypoxia on neuroretinal function in two different age groups.
  
  
  METHODS
  The slow-flash paradigm of the multifocal electroretinogram (mfERG) was measured in two different oxygenation levels. Twelve participants of two age groups (28 +/- 4 and 55 +/- 5 years) breathed room air (normoxia) or 12% oxygen (hypoxia).
  
  
  RESULTS
  During normoxia (SaO(2) = 98%) there was a significantly different effect between the younger and older participants on the mfERG positive waveform components (N1P1 amplitudes and P1 implicit times; P < 0.001). Hypoxia (SaO(2) = 90%) significantly decreased N1P1 response density amplitudes in the central retinal field in both groups, with a larger effect in the older group (P < 0.001). There was no significant change in function of the cellular generators of oscillatory potentials (OPs).
  
  
  CONCLUSIONS
  The results extend recent findings by showing a greater effect of hypoxia on ON- and OFF-bipolar cell function in healthy older persons than in younger persons, but no effect on OPs during moderate acute hypoxia in either age group.
authors.affiliation: Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia. b.feigl@qut.edu.au
authors.forename: Beatrix
authors.initials: B
authors.lastname: Feigl
authors.forename: Ian B
authors.initials: IB
authors.lastname: Stewart
authors.forename: Brian
authors.initials: B
authors.lastname: Brown
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Zele
mesh_terms: D000208:Acute Disease; D000328:Adult; D000375:Aging / Q000502:physiology*; D004596:Electroretinography; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage; D012160:Retina / Q000503:physiopathology*; D051245:Retinal Bipolar Cells / Q000502:physiology
chemical_list: D010100:Oxygen