Effect of NCAM on aged-related deterioration in vision.
The neural cell adhesion molecule (NCAM) is involved in developmental processes and age-associated cognitive decline; however, little is known concerning the effects of NCAM in the visual system during aging. Using anatomical, electrophysiological, and behavioral assays, we analyzed age-related changes in visual function of NCAM deficient (-/-) and wild-type mice. Anatomical analyses indicated that aging NCAM -/- mice had fewer retinal ganglion cells, thinner retinas, and fewer photoreceptor cell layers than age-matched controls. Electroretinogram testing of retinal function in young adult NCAM -/- mice showed a 2-fold increase in a- and b-wave amplitude compared with wild-type mice, but the retinal activity dropped dramatically to control levels when the animals reached 10 months. In behavioral tasks, NCAM -/- mice had no visual pattern discrimination ability and showed premature loss of vision as they aged. Together, these findings demonstrate that NCAM plays significant roles in the adult visual system in establishing normal retinal anatomy, physiology and function, and in maintaining vision during aging.
Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada.
Margaret Po-Shan
MP
Luke
Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada.
Terry L
TL
LeVatte
Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada.
Amanda M
AM
O'Reilly
Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada.
Benjamin J
BJ
Smith
Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada.
François
F
Tremblay
Department of Psychology and Neuroscience, Life Science Centre, Dalhousie University, Halifax, Nova Scotia, Canada.
Richard E
RE
Brown
Department of Medical Neuroscience, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Surgery (Neurosurgery), Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Medicine (Endocrinology), Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Ophthalmology & Visual Sciences, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada. Electronic address: d.clarke@dal.ca.
David B
DB
Clarke
D000375:Aging / Q000235:genetics* / Q000473:pathology / Q000502:physiology*; D000818:Animals; D019002:CD56 Antigen / Q000235:genetics / Q000378:metabolism*; D004596:Electroretinography; D005260:Female; D008297:Male; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010786:Photoreceptor Cells / Q000473:pathology; D012160:Retina / Q000166:cytology / Q000378:metabolism / Q000473:pathology / Q000502:physiology; D014786:Vision Disorders / Q000209:etiology* / Q000235:genetics* / Q000473:pathology; D014785:Vision, Ocular / Q000235:genetics* / Q000502:physiology*
D019002:CD56 Antigen; C501063:Ncam1 protein, mouse
Aging; Neural cell adhesion molecule (NCAM); Polysialic acid (PSA); Retina; Visual system