title: Comparison on photopic electroretinogram negative response between young and old Lewis rats.
abstract: OBJECTIVE
  To investigate and compare the latency and amplitude of the electroretinogram (ERG) photopic negative response (PhNR) between young and old Lewis rats.
  
  
  METHODS
  Thirteen Lewis rats were divided into two groups according to ages, young group (3-month old n=5) and old group (24 month old n=8). The ERGs of the left eyes were measured and the latency and amplitude of a-wave, b-wave and PhNRs were recorded and compared according to ages. The mean values between two groups were statistically analysed by t-test.
  
  
  RESULTS
  The latency of PhNRs were evidently prolonged in old group and showed significant difference (P<0.05). There was no statistically significant difference between two groups regarding the amplitude and latency, and no significant difference was noted in the amplitude of PhNRs.
  
  
  CONCLUSIONS
  The prolonged latency of PhNR in aged rats possibly associate with the influence of aging upon retinal ganglion cell layer (RGCL).
authors.affiliation: Chinese Universtiy of Hong Kong Joint Shantou International Eye Center, Shantou, China.
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Geng
authors.forename: Hongling
authors.initials: H
authors.lastname: Chen
authors.forename: Lifang
authors.initials: L
authors.lastname: Liu
authors.forename: Hongjie
authors.initials: H
authors.lastname: Lin
authors.forename: Mingzhi
authors.initials: M
authors.lastname: Zhang
mesh_terms: D000367:Age Factors; D000375:Aging / Q000502:physiology; D000818:Animals; D004596:Electroretinography; D006801:Humans; D051381:Rats; D011917:Rats, Inbred Lew; D011930:Reaction Time / Q000502:physiology*; D012160:Retina / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000502:physiology*