title: TRPV1 receptor in the human trigeminal ganglion and spinal nucleus: immunohistochemical localization and comparison with the neuropeptides CGRP and SP.
abstract: This work presents new data concerning the immunohistochemical occurrence of the transient receptor potential vanilloid type-1 (TRPV1) receptor in the human trigeminal ganglion (TG) and spinal nucleus of subjects at different ontogenetic stages, from prenatal life to postnatal old age. Comparisons are made with the sensory neuropeptides calcitonin gene-related peptide (CGRP) and substance P (SP). TRPV1-like immunoreactive (LI) material was detected by western blot in homogenates of TG and medulla oblongata of subjects at prenatal and adult stages of life. Immunohistochemistry showed that expression of the TRPV1 receptor is mostly restricted to the small- and medium-sized TG neurons and to the caudal subdivision of the spinal trigeminal nucleus (Sp5C). The extent of the TRPV1-LI TG neuronal subpopulation was greater in subjects at early perinatal age than at late perinatal age and in postnatal life. Centrally, the TRPV1 receptor localized to fibre tracts and punctate elements, which were mainly distributed in the spinal tract, lamina I and inner lamina II of the Sp5C, whereas stained cells were rare. The TRPV1 receptor colocalized partially with CGRP and SP in the TG, and was incompletely codistributed with both neuropeptides in the spinal tract and in the superficial laminae of the Sp5C. Substantial differences were noted with respect to the distribution of the TRPV1-LI structures described in the rat Sp5C and with respect to the temporal expression of the receptor during the development of the rat spinal dorsal horn. The distinctive localization of TRPV1-LI material supports the concept of the involvement of TRPV1 receptor in the functional activity of the protopathic compartment of the human trigeminal sensory system, i.e. the processing and neurotransmission of thermal and pain stimuli.
authors.affiliation: Department of Biomedical Sciences, Cytomorphology Section, University of Cagliari, Monserrato (CA), Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Quartu
authors.affiliation: Department of Biomedical Sciences, Cytomorphology Section, University of Cagliari, Monserrato (CA), Italy.
authors.forename: Maria Pina
authors.initials: MP
authors.lastname: Serra
authors.affiliation: Department of Biomedical Sciences, Cytomorphology Section, University of Cagliari, Monserrato (CA), Italy.
authors.forename: Marianna
authors.initials: M
authors.lastname: Boi
authors.affiliation: Department of Biomedical Sciences, Cytomorphology Section, University of Cagliari, Monserrato (CA), Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Poddighe
authors.affiliation: Department of Biomedical Sciences, Cytomorphology Section, University of Cagliari, Monserrato (CA), Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Picci
authors.affiliation: Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Demontis
authors.affiliation: Department of Biomedical Sciences, Cytomorphology Section, University of Cagliari, Monserrato (CA), Italy.
authors.forename: Marina
authors.identifier: 0000-0003-4104-4328
authors.initials: M
authors.lastname: Del Fiacco
mesh_terms: D000328:Adult; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis* / Q000235:genetics; D002648:Child; D005260:Female; D005333:Fetus; D006801:Humans; D008297:Male; D008875:Middle Aged; D009479:Neuropeptides / Q000032:analysis / Q000235:genetics; D011247:Pregnancy; D051381:Rats; D013373:Substance P / Q000032:analysis* / Q000235:genetics; D050916:TRPV Cation Channels / Q000032:analysis* / Q000235:genetics; D012668:Trigeminal Ganglion / Q000737:chemistry*; D014279:Trigeminal Nucleus, Spinal / Q000737:chemistry*
chemical_list: D009479:Neuropeptides; D050916:TRPV Cation Channels; C494482:TRPV1 protein, human; D013373:Substance P; D015740:Calcitonin Gene-Related Peptide
keywords: calcitonin gene-related peptide; human trigeminal system; immunohistochemistry; substance P; transient receptor potential vanilloid type-1 receptor; western blot