The effects of light and dark adaptation on the levels of cyclic nucleotides in retinas of mice heterozygous for a gene for photoreceptor dystrophy

Abstract

Levels of cyclic AMP and cyclic GMP were measured in light and dark adapted retinas from normal mice (++/++) and from mice heterozygous for the photoreceptor dystrophy gene (rdle/++). In light adapted retinas cyclic GMP levels were 40% lower in the heterozygotes than in the normals, whereas cyclic AMP levels were the same. Dark adaptation elevated cyclic GMP levels 120% in both groups and also elevated cyclic AMP levels 90% in the ++/++ and 45% in the heterozygotes. These data suggest that animals heterozygous for photoreceptor dystrophy have an abnormality of their retinal cyclic GMP system.