title: Comparison of electroretinographic responses between two different age groups of adult Dark Agouti rats.
abstract: OBJECTIVE
  To describe and compare the differences in electroretinographic responses between two different age groups of adult Dark Agouti (DA) rats and to better understand the effect of age on retinal histology and function.
  
  
  METHODS
  The electroretinographic responses of two different age groups of adult DA rats were compared. Animals were divided into younger adult DA rats 10-12wk (n=8) and older adult DA rats 17-19wk (n=8). Full field electroretinography (ERG) was recorded simultaneously from both eyes after dark adaption and light adaption and parameters including the positive scotopic threshold response (pSTR), negative scotopic threshold response (nSTR), scotopic a-wave, b-wave, photopic a-wave, b-wave and photopic negative response (PhNR) were compared between groups.
  
  
  RESULTS
  The older adult rats displayed lower stimulation thresholds of the STRs (pSTR and nSTR) and higher amplitudes of pSTR, scotopic a-wave and b-wave, photopic b-wave and PhNR amplitudes, with shorter implicit times. Photopic a-wave amplitudes were however higher in the younger adult rats.
  
  
  CONCLUSIONS
  In summary, for the rod system, photoreceptor, bipolar cell and RGC activity was enhanced in the older adult rats. For the cone system, RGC and bipolar cell activity was enhanced, while photoreceptor activity was depressed in the older adult rats. Such age-related selective modification of retinal cell function needs to be considered when conducting ophthalmic research in adult rats.
authors.affiliation: Department of Ophthalmology, LKS Faculty of Medicine, University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Fu
authors.affiliation: Department of Ophthalmology, LKS Faculty of Medicine, University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Amy Cheuk Yin
authors.initials: AC
authors.lastname: Lo
authors.affiliation: Department of Ophthalmology, LKS Faculty of Medicine, University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Jimmy Shiu Ming
authors.initials: JS
authors.lastname: Lai
authors.affiliation: Department of Ophthalmology, LKS Faculty of Medicine, University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Kendrick Co
authors.initials: KC
authors.lastname: Shih
keywords: Dark Agouti rats; age; electroretinographic responses