title: Projections from the raphe nuclei to the phrenic motor nucleus in the cat.
abstract: The purpose of this study was to identify the projections from the brain to the phrenic motor nucleus in the cat by employing a retrogradely-transported fluorescent dye. Propidium iodide was iontophoresed into the phrenic motor nucleus which is located in the fourth, fifth and sixth segments of the cervical spinal cord. Retrogradely-labeled cell bodies were found in the brainstem within recognized respiratory areas. In addition, retrogradely-labeled cell bodies were found within the raphe nuclei, nuclear areas not previously associated with respiratory control. The results of this study suggest that the raphe nuclei may play a role in the central regulation of breathing.
mesh_terms: D000818:Animals; D001933:Brain Stem / Q000166:cytology*; D002415:Cats; D005727:Ganglia, Spinal / Q000166:cytology*; D009046:Motor Neurons / Q000502:physiology; D010791:Phrenic Nerve / Q000166:cytology*; D011903:Raphe Nuclei / Q000166:cytology*; D012119:Respiration