Enkephalins occur and colocalize with substance P in human trigeminal ganglion neurones.
Immunohistochemical evidence is provided for (i) the occurrence of a primary sensory neuronal population immunoreactive to methionine- and leucine-enkephalin (EK) in the human trigeminal ganglion; (ii) colocalization of EK and substance P (SP) in a subpopulation of ganglion neurones and in nerve fibres and terminal-like structures in the human trigeminal spinal nucleus. The results obtained indicate that part of the EK-positive innervation of the spinal nucleus may be of ganglionic origin and raise the possibility that EK and SP are co-stored in and co-released from primary afferent terminals, thus adding to the complexity of the sites and ways of interaction between these neuropeptides in the processing of sensory information.
Quartu
M
M
Dipartimento di Citomorfologia, University of Cagliari, Italy.
Del Fiacco
M
M
D000328:Adult; D000368:Aged; D004745:Enkephalins / Q000032:analysis*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000737:chemistry; D013373:Substance P / Q000032:analysis*; D012668:Trigeminal Ganglion / Q000737:chemistry* / Q000166:cytology; D014279:Trigeminal Nucleus, Spinal / Q000737:chemistry
D004745:Enkephalins; D013373:Substance P