[Light response of the interphotoreceptor matrix in inherited degenerative retina]

The light-evoked distributional changes of the interphotoreceptor matrix (IPM) in mice with three types of inherited retinal degeneration were examined by histochemistry using fluorescence isocyanate-labeled wheat germ agglutinin. In mice with nervous and Purkinje cell degeneration, the light response of the IPM was still somewhat preserved during the early stage of photoreceptor degeneration, whereas it became extinct when the outer segments (OS) became moderately or markedly shortened. In mice with slow retinal degeneration mice without development of OS, the light response of the IPM was absent throughout the developmental stages. These findings suggest that the presence of normal OS is necessary for the light response of the IPM to occur.