Benzodiazepine receptors in the eye.

Central and peripheral benzodiazepine receptors were localized in the rat, monkey, and human eye by in vitro autoradiography. Central benzodiazepine binding sites, visualized with 3H-R015-1788, were enriched in the inner plexiform layer in all three species. Binding sites also were present in the nerve fiber layer, the ganglion cell layer, and in portions of the inner nuclear layer. Peripheral benzodiazepine binding sites, visualized with 3H-PK-11195, were found in the corneal epithelium and endothelium, iris, ciliary epithelium, trabecular meshwork, and throughout the retina. Binding sites for 3H-PK-11195 also were present in the retinal pigment epithelium and choriocapillaris areas and retinal vascular structures.