Localization of substance P immunoreactivity in phrenic primary afferent neurons.
Retrograde tracing with a fluorescent dye (Fast Blue) combined with immunohistochemistry was used to localize the putative neurotransmitter, substance P, in phrenic primary afferent neurons. Fast Blue was injected into the diaphragm and was found to label phrenic primary afferent neurons in sections from the fifth and sixth cervical dorsal root ganglia. The same sections were then treated with antiserum to substance P. A total of 11.4% of labelled phrenic primary afferent neurons contained substance P immunoreactivity. The diameters of the neurons ranged between 17 to 45 microns with a mean size of 29.7 +/- 0.7 microns (N = 81). The results suggest that substance P could be involved in mediating the transmission of sensory information from the diaphragm to the CNS.
Holtman
J R
JR
Department of Pharmacology, College of Medicine, University of Kentucky, Lexington 40536.
D000344:Afferent Pathways / Q000166:cytology*; D000818:Animals; D001370:Axonal Transport; D002415:Cats; D005455:Fluorescent Antibody Technique; D005727:Ganglia, Spinal / Q000166:cytology*; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000166:cytology*; D010791:Phrenic Nerve / Q000166:cytology*; D013373:Substance P / Q000032:analysis*
D013373:Substance P