title: Immunocytochemical demonstration of pituitary adenylate cyclase activating polypeptide (PACAP) in the porcine epiphyseal cartilage canals.
abstract: Pituitary adenylate cyclase activating polypeptide (PACAP), a member of the vasoactive intestinal polypeptide (VIP)/secretin/glucagon family, is known to be a powerful stimulator of adenylate cyclase. Recently, PACAP has been shown to stimulate cAMP in osteoblast-like cells and mouse calvarian bones. In the present study, PACAP immunoreactivity (IR) was demonstrated in cartilage canals from newborn and 3-4-week-old pigs. In tissues from the femoral head and the patella with and without ossification centres, PACAP-IR nerve fibres were found in the cartilage canals innervating blood vessels. The pattern of distribution was not dependent on age or the occurrence of an ossification centre. Co-localization studies showed a high degree of co-localization with calcitonin gene-related peptide (CGRP) and substance P (SP) but little co-localization with VIP. Our findings support earlier findings of CGRP, SP and VIP in bone tissue and add PACAP to the group of neuropeptides with a sensory and/or modulatory function in bone tissue.
authors.affiliation: Dept. of Orthopaedics, Rigshospitalet, University of Copenhagen, Denmark.
authors.forename: H H
authors.initials: HH
authors.lastname: Strange-Vognsen
authors.forename: J
authors.initials: J
authors.lastname: Arnbjerg
authors.forename: J
authors.initials: J
authors.lastname: Hannibal
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis; D005260:Female; D005269:Femur; D006132:Growth Plate / Q000166:cytology* / Q000294:innervation*; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008856:Microscopy, Fluorescence; D009412:Nerve Fibers / Q000648:ultrastructure*; D009479:Neuropeptides / Q000032:analysis*; D018377:Neurotransmitter Agents / Q000032:analysis; D010329:Patella; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D013373:Substance P / Q000032:analysis; D013552:Swine; D014660:Vasoactive Intestinal Peptide / Q000032:analysis
chemical_list: C495402:Adcyap1 protein, mouse; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D015740:Calcitonin Gene-Related Peptide