The melanocytotoxicity of gamma-L-glutaminyl-4-hydroxybenzene: a study of the pigmented cells in the mouse eye.

The administration of gamma-L-glutaminyl-4-hydroxybenzene (GHB) to neonatal black mice resulted in selective necrosis of the melanocytes in the choroid but had no apparent effect on the retinal pigment epithelium and pigmented cells of the iris and ciliary body. No changes were noted in any of the ocular melanocytes when GHB was administered to adult black mice or neonatal albino mice. The administration of p-aminophenol, which may be a metabolite of GHB in mammalian cells, produced identical cytologic changes in the eyes of neonatal black mice. The findings indicate that in the presence of an active melanogenic environment, the metabolism of GHB generates products that are promptly cytolytic. In the immature retina of both black and albino mice, the administration of GHB also resulted in scattered necrosis in the inner layer of the developing neuroblastic cells in the form of cellular condensation. This effect, which is independent of the process of melanogenesis, could not be elicited beyond the fifth postnatal day and may represent a quantitative exaggeration of a normal cellular phenomenon.