title: Visceral and somatic afferent origin of calcitonin gene-related peptide immunoreactivity in the lower thoracic spinal cord of the rat.
abstract: The origin of calcitonin gene-related peptide in the thoracic spinal cord of the rat was investigated by radioimmunoassay and immunohistochemistry. In transverse sections from normal animals there was a dense staining of calcitonin gene-related peptide-immunoreactivity in laminae I, II and V of the dorsal horn. In parasagittal sections this was found to consist of rostrocaudally orientated fibres in laminae I and II and longitudinal bundles of fibres interspersed with a plexus of immunoreactivity in lamina V. After sectioning the thoracic spinal nerves there was a significant reduction in immunoreactivity in the dorsal horn of the spinal cord which was seen as a marked reduction of staining in lamina II and in the bundles of fibres in lamina V. Section of the splanchnic nerve slightly reduced staining in lamina I and virtually abolished the plexuses of immunoreactivity in lamina V. However, measurement of calcitonin gene-related peptide in samples from coeliac-ganglionized rats revealed an increase in immunoreactivity in regions of the spinal cord containing lamina V. These results provide evidence of a visceral and somatic afferent origin of calcitonin gene-related peptide in the thoracic spinal cord of the rat.
authors.affiliation: Department of Physiology, Medical School, University of Bristol, U.K.
authors.forename: K A
authors.initials: KA
authors.lastname: Sharkey
authors.forename: J A
authors.initials: JA
authors.lastname: Sobrino
authors.forename: F
authors.initials: F
authors.lastname: Cervero
authors.forename: A
authors.initials: A
authors.lastname: Varro
authors.forename: G J
authors.initials: GJ
authors.lastname: Dockray
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D009475:Neurons, Afferent / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000166:cytology / Q000378:metabolism*
chemical_list: D015740:Calcitonin Gene-Related Peptide