The corneal ERG of the heterozygous retinal degeneration mouse.
In the retina of the mouse heterozygous for retinal degeneration (+ rd) cGMP levels are reported to be considerably reduced from normal. The sensitivity and timing of the a- and b-wave components of the electroretinogram of anaesthetized, dark-adapted, heterozygous (+ rd) mice were measured and compared with those of normals (+ +). The (+ rd) mouse was found to be 0.43 log units more sensitive to flashes of green light than the normal for both a- and b-waves; the Vmax amplitude of the b-wave was larger; and variations in time-to-peak were of small magnitude except at low a-wave intensities, where the + rd responses were slowed compared with those of + +. Reduced phosphodiesterase activity has been suggested previously as a mechanism for altered cGMP levels in the rd mouse. The findings reported are interpreted in terms of reduced rates of cGMP metabolism.
Low
J C
JC
Department of Visual Science, Institute of Ophthalmology, London, England.
D000818:Animals; D006152:Cyclic GMP / Q000378:metabolism; D004596:Electroretinography; D006579:Heterozygote; D051379:Mice; D008810:Mice, Inbred C57BL; D012160:Retina / Q000503:physiopathology; D012162:Retinal Degeneration / Q000235:genetics* / Q000503:physiopathology
D006152:Cyclic GMP