title: Dynorphin A: in vivo release in the spinal cord of the cat.
abstract: The antibody microprobe technique was used to study the release of immunoreactive dynorphin A within the lower lumbar spinal cord of anaesthetised cats. A basal release was observed in the dorsal horn, centered in the region of lamina I, but was abolished by spinal cord transection at the thoracolumbar junction. Release of dynorphin A in the lamina I region was evoked by high-frequency electrical stimulation of unmyelinated primary afferent fibres, whereas stimulation of myelinated (including A delta) afferents was ineffective. Evidence was also obtained for release in laminae V-VI and at the spinal cord surface. These results suggest that in the lumbar spinal cord of the cat, dynorphin A is released in the superficial dorsal horn by impulses in descending pathways and in somatic unmyelinated primary afferent fibres.
authors.affiliation: Physiologisches Institut der Universität Würzburg, F.R.G.
authors.forename: W D
authors.initials: WD
authors.lastname: Hutchison
authors.forename: C R
authors.initials: CR
authors.lastname: Morton
authors.forename: L
authors.initials: L
authors.lastname: Terenius
mesh_terms: D000344:Afferent Pathways / Q000378:metabolism; D000818:Animals; D002415:Cats; D003655:Decerebrate State; D004399:Dynorphins / Q000378:metabolism*; D004558:Electric Stimulation; D007150:Immunohistochemistry; D008161:Lumbosacral Region; D015335:Molecular Probes; D009413:Nerve Fibers, Myelinated / Q000378:metabolism*; D010525:Peripheral Nerves / Q000502:physiology; D013116:Spinal Cord / Q000378:metabolism*
chemical_list: D015335:Molecular Probes; D004399:Dynorphins