Proctolin immunoreactive neurons in the human brain stem

Using the peroxidase-antiperoxidase (PAP) technique it could be established that a variety of nerve cells of human Pons and Medulla oblongata contain proctolin-like material. These neurons belong to the Nuc. olivaris caudalis, Nuc. originis n. hypoglossi, Nuc. raphes dorsalis and the Nuc. ambiguus. Furthermore, proctolin immunoreactive peptide was found to be contained in certain fiber systems (Lemniscus medialis and fiber tracts near the Raphe).