title: Targeted disruption of the galanin gene reduces the number of sensory neurons and their regenerative capacity.
abstract: The neuropeptide galanin is expressed developmentally in the dorsal root ganglion (DRG) and is rapidly up-regulated 120-fold after peripheral nerve section in the adult. Here we report that adult mice carrying a loss-of-function mutation in the galanin gene have a 13% reduction in the number of cells in the DRG associated with a 24% decrease in the percentage of neurons that express substance P. These deficits are associated with a 2.8- and 2.6-fold increase in the number of apoptotic cells in the DRG at postnatal days 3 and 4, respectively. After crush injury to the sciatic nerve, the rate of peripheral nerve regeneration is reduced by 35% with associated long-term functional deficits. Cultured DRG neurons from adult mutant mice demonstrate similar deficits in neurite number and length. These results identify a critical role for galanin in the development and regeneration of sensory neurons.
authors.affiliation: Departments of Medicine and Oral and Dental Science, Bristol University, Marlborough Street, Bristol BS2 8HW, United Kingdom.
authors.forename: F E
authors.initials: FE
authors.lastname: Holmes
authors.forename: S
authors.initials: S
authors.lastname: Mahoney
authors.forename: V R
authors.initials: VR
authors.lastname: King
authors.forename: A
authors.initials: A
authors.lastname: Bacon
authors.forename: N C
authors.initials: NC
authors.lastname: Kerr
authors.forename: V
authors.initials: V
authors.lastname: Pachnis
authors.forename: R
authors.initials: R
authors.lastname: Curtis
authors.forename: J V
authors.initials: JV
authors.lastname: Priestley
authors.forename: D
authors.initials: D
authors.lastname: Wynick
mesh_terms: D000818:Animals; D001369:Axons; D019004:Galanin / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D009416:Nerve Regeneration; D009475:Neurons, Afferent / Q000166:cytology* / Q000502:physiology*
chemical_list: D019004:Galanin