title: Expression of neuropeptides and growth-associated protein 43 (GAP-43) in cutaneous and mucosal nerve structures of the adult rat lower lip after mental nerve section.
abstract: The reinnervation of the adult rat lower lip has been investigated after unilateral section of the mental nerve. Rats were sacrificed at 4, 7, 9, 14, 30, and 90 days after the operation. A further group of animals with section of the mental nerve and block of the alveolar nerve regeneration, was sacrificed at 14 days. Specimens were processed for immunocytochemistry with antibodies against PGP 9.5, GAP-43 or neuropeptides (CGRP, SP and VIP). Four days after nerve section, axonal degeneration seems evident in the mental nerve branches and inside skin and mucosa. GAP-43 immunoreactivity is intense in the mental nerve 7 days after nerve section and it reaches its maximal expression and distribution in peripheral nerve fibres at 14 days. At 30 days, the decline in its expression is associated with the increase of PGP9.5-, SP-, and CGRP immunopositivity. VIP is observed only in perivascular fibres at all times observed. Present results suggest that, after sensory denervation of the rat lip, nerve fibres in skin and mucosa remain at lower density than normal. The different time courses in the expression of neuropeptides and GAP-43 suggest a possible early involvement of GAP-43 in peripheral nerve regeneration.
authors.affiliation: Laboratory of Neuroendocrinology, Department of Anatomy, Pharmacology and Forensic Medicine, University of Torino, Corso Massimo D'Azeglio 52, I-10126 Torino, Italy. laura.verze@unito.it
authors.forename: L
authors.initials: L
authors.lastname: Verzè
authors.forename: A
authors.initials: A
authors.lastname: Paraninfo
authors.forename: C
authors.initials: C
authors.lastname: Viglietti-Panzica
authors.forename: G C
authors.initials: GC
authors.lastname: Panzica
authors.forename: G
authors.initials: G
authors.lastname: Ramieri
mesh_terms: D000818:Animals; D003714:Denervation; D005260:Female; D005539:Foramen Magnum / Q000187:drug effects / Q000502:physiology; D019922:GAP-43 Protein / Q000378:metabolism*; D007150:Immunohistochemistry; D008046:Lip / Q000294:innervation*; D009061:Mouth Mucosa / Q000166:cytology / Q000294:innervation* / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000166:cytology*; D013869:Thiolester Hydrolases / Q000032:analysis; D013997:Time Factors; D043222:Ubiquitin Thiolesterase
chemical_list: D019922:GAP-43 Protein; D009479:Neuropeptides; D013869:Thiolester Hydrolases; D043222:Ubiquitin Thiolesterase