Distribution of glycine-immunoreactive cell bodies and fibers in the rat brain (original) (raw)

To localize glycinergic cell bodies and fibers in the rat brain, we developed a sensItive immunohistochemical method combining the use of specific glycine antibodies (Campistron G. et al. (1986) Brain Res. 376, 400-405; Neuroscience 22, 897-912) with the streptavidin-horseradish peroxidase technique and 3,3'-diaminobenzidine'4HCI-nickel intensification. We confirmed the presence of numerous glycine-immunoreactive cell bodies and fibers in the cochlear nuclei, superior olivary complex, nucleus of the trapezoid body, cerebellar cortex, deep cerebellar nuclei and area postrema. For the first time in rats, we described a large to very large number of cell bodies in the medial vestibular ventral part, prepositus hypoglossal, gracile, raphe magnus and sensory trigeminal nuclei. A large number of cells was also observed in the oral and caudal pontine, parvocellular, parvocellular pars alpha, gigantocellular and gigantocellular pars alpha reticular nuclei. In addition, glycine-immunoreactive cells were seen in the ambiguus and subtrigeminal nuclei, the lateral habenula and the subfomical organ. We also provide the first evidence in rats for a very large number of fibers in the trigeminal, facial, ambiguus and hypoglossal motor nuclei, all nuclei of the medullary and pontine reticular formation, and the raphe and trigeminal sensory nuclei. We further revealed the presence of a substantial number of fibers in regions where glycine was not considered as a main inhibitory neurotransmitter, such as the pontine nuclei, the periaqueductal gray, the mesencephalic reticular formation, the anterior pretectal nucleus, the intralaminar thalamic nuclei, the zona incerta, the fields of Forel, the parvocellular parts of the paraventricular nucleus, the posterior hypothalamic areas, the anterior hypothalamic area, and the lateral and medial preoptic areas.