‘Brain-specific’ benzodiazepine receptors are localized in the inner plexiform layer of rat retina

Saturable, high affinity binding sites of [³H]diazepam have recently been characterized in rat brain. A significant component of this binding was determined to occur to a population of receptors which is pharmacologically similar to receptors present in mammalian brain and spinal cord. Neonatal treatment of rats with monosodium glutamate (MSG), intraocular administration of kainic acid, and the use of pink-eyed, tan-hooded (PETH) rats with a genetic retinopathy (degeneration of photoreceptor cells) suggests that these ‘brain-type’ receptors are highly localized on neuronal elements of the inner plexiform layer and/or ganglion cells.