title: Evidence for periaqueductal cholecystokinin-substance P neurons projecting to the spinal cord.
abstract: Using indirect immunofluorescence techniques combined with retrogradely transported fluorescent dyes, cholecystokinin (CCK)-like and substance P immunoreactive cell bodies in the periaqueductal central grey of the rat brain were studied. Data from both adjacent sections and elution-restaining techniques indicated that some of these central grey cells contain both a CCK-like peptide and substance P. Injection of the fluorescent dye, Fast Blue, into the cervical spinal cord indicated that this CCK-substance P cell group is a descending system. These findings provide evidence for two peptides in a single neuron, and the possible functional significance of such an occurrence is discussed.
mesh_terms: D000818:Animals; D002766:Cholecystokinin / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D006168:Guinea Pigs; D008297:Male; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000502:physiology*; D010487:Periaqueductal Gray / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000502:physiology*; D013373:Substance P / Q000502:physiology*
chemical_list: D013373:Substance P; D002766:Cholecystokinin