Differential effect of the rd mutation on rods and cones in the mouse retina.
The retinas of rd/rd C57BL/6J-rd le mice have been examined by light and electron microscopy to determine whether rod cell degeneration precedes cone cell degeneration. In all regions of the eye, a rapid rod degeneration precedes a much slower cone degeneration. Only about 2% of the rods remain in the posterior region at postnatal day 17, and none by the day 36. By contrast, at least 75% of the cone nuclei remain at day 17. Although most of these slowly disappear, about 1.5% of the original population of cone nuclei in the posterior retina is still present at 18 months of age. A central to peripheral temporal gradient of degeneration exists, such that some rod nuclei persist in the far periphery up to day 47, but none is found at day 65. About 5% of the cone nuclei are still present in the far periphery at 18 months of age.
D000367:Age Factors; D000818:Animals; D005260:Female; D005808:Genes, Recessive; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation; D010786:Photoreceptor Cells / Q000002:abnormalities* / Q000473:pathology / Q000648:ultrastructure; D012162:Retinal Degeneration / Q000151:congenital* / Q000473:pathology