Immunocytochemical evidence for the involvement of glycine in sensory centers of the rat brain.

Glycine-like immunoreactivity was localized to a number of sites in the rat brain which are involved in processing sensory information. In the auditory and vestibular systems, glycine immunoreactivity was seen in dorsal and ventral cochlear nuclei, superior olive, trapezoid body, medial and lateral vestibular nuclei, and inferior colliculus. Staining in the visual system was seen in retina, dorsal lateral geniculate nucleus, and superior colliculus. The olfactory system exhibited staining in the olfactory bulb and accessory olfactory formation. Somatosensory centers with glycine immunoreactivity included the dorsal column nuclei, spinal trigeminal nucleus, principal sensory nucleus of V, reticular formation, and periaqueductal gray. Glycine-immunoreactive neurons were also seen in cerebellar cortex, deep cerebellar nuclei, hippocampus, cerebral cortex, and striatum. The distribution of staining indicates that glycine plays a major role in sensory centers with actions at both strychnine-sensitive and strychnine-insensitive receptors.