Changes of lysosomal enzymes during hereditary degeneration and histogenesis of retina in mice

Summary

During the post-natal development of the retina in mice, macrophages which are selectively stained for N-Acetyl-β-glucosaminidase enter the retina through the vascular route. Most of these cells finally occupy the outer and the inner levels of the inner nuclear layer adjoining the plexiform layers and are transformed into very small cells which persist in the adult retina without further change.

In mice with hereditary retinal degeneration (rd rd) these β-glucosaminidase positive macrophages enter the outer nuclear layer of the retina, soon after the onset of degeneration undergo extensive hypertrophy and rapidly phagocytize the degenerating photoreceptor cells. After the digestion of the ingested materials the enzyme activity is very much reduced and the cells become smaller in size. They eventually acquire the morphological features seen in the normal retina.