Immunocytochemical localization of ornithine aminotransferase in human ocular tissues

T. Mito, T. Shiono, S. Ishiguru, M. Tamai, K. Mizuno and T. Ohura
Department of Ophthalmology, University School of Medicine, Sendai, Japan.

Gyrate atrophy of the choroid and retina is a rare inherited form chorioretinal degeneration caused by a deficiency of ornithine aminotransferase. We localized the enzyme in human ocular tissues using immunocytochemical procedures. Immunoreactivity was observed in the nonpigmented epithelium of the ciliary body and lens epithelium. In the retina, ganglion cells and some amacrine cells were immunoreactive. Pigmented granules made it difficult to identify immunoreactive products in the iris, pigmented epithelium of the ciliary body, choroid, and retinal pigment epithelium. Our findings suggested that ornithine aminotransferase plays an important role in ornithine metabolism in these oculartissues.