Immunohistochemical localization of calretinin in the rat hindbrain

The localization of calretinin in the rat hindbrain was examined immunohistochemically with an antiserum against calretinin purified from the guinea pig brain. Calretinin immunoreactivity was found within neuronal elements. The distribution of calretinin‐immunoreactive cell bodies and fibers is presented in schematic drawings and summarized in a table. Major calretinin immunoreactive neurons were found in the lateral and medial geniculate nuclei, substantia nigra, ventral tegmental area, interpeduncular nucleus, periaqueductal gray, mesencephalic trigeminal nucleus, superior and inferior colliculi, pontine nuclei, parabrachial nucleus, dorsal and laterodorsal tegmental nuclei, cochlear nuclei, vestibular nuclei, medullary reticular nuclei, nucleus of the solitary tract, area postrema, substantia gelatinosa of the spinal trigeminal nucleus, and cerebellum. These results show that distinct calretinin‐immunoreactive neurons are widely distributed in the rat hindbrai.