[Quantitative effects of retinal degeneration in mice]

The thickness of two layers of the retina (the inner plexiform layer and the inner nuclear layer), together with the density of cells in the ganglion cell layer, were measured in a sample of mice from a population segregating for albinism and retinal degeneration. The expression of retinal degeneration was found to involve not only the disappearance of retinal receptors but also a reduction in thickness of the inner plexiform layer and a reduction of cell density in the ganglion cell layer: these changes were found to be associated with a reduction of neuronal density in the lateral geniculate nucleus, but not in the superior colliculus. The expression of retinal degeneration was also found to be unaffected either by albinism or by dark-rearing.