title: Axotomy-induced expression of calcium-activated chloride current in subpopulations of mouse dorsal root ganglion neurons.
abstract: Whole cell patch-clamp recordings of calcium-activated chloride current [ICl(Ca)] were made from adult sensory neurons of naive and axotomized mouse L4-L6 lumbar dorsal root ganglia after 1 day of culture in vitro. A basal ICl(Ca) was specifically expressed in a subset of naive medium-diameter neurons (30-40 microm). Prior nerve injury, induced by sciatic nerve transection 5 days before experiments, increased both ICl(Ca) amplitude and its expression in medium-diameter neurons. Moreover, nerve injury also induced ICl(Ca) expression in a new subpopulation of neurons, the large-diameter neurons (40-50 microm). Small-diameter neurons (inferior to 30 microm) never expressed ICl(Ca). Regulated ICl(Ca) expression was strongly correlated with injury-induced regenerative growth of sensory neurons in vitro and nerve regeneration in vivo. Cell culture on a substrate not permissive for growth, D,L-polyornithine, prevented both elongation growth and ICl(Ca) expression in axotomized neurons. Regenerative growth and the induction of ICl(Ca) expression take place 2 days after injury, peak after 5 days of conditioning in vivo, slowly declining thereafter to control values. The selective expression of ICl(Ca) within medium- and large-diameter neurons conditioned for rapid, efficient growth suggests that these channels play a specific role in postinjury behavior of sensory neuron subpopulations such as neuropathic pain and/or axonal regeneration.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale U-583, Université Montpellier II, 34095, Montpellier 5, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: André
authors.forename: Hassan
authors.initials: H
authors.lastname: Boukhaddaoui
authors.forename: Brice
authors.initials: B
authors.lastname: Campo
authors.forename: Mohammed
authors.initials: M
authors.lastname: Al-Jumaily
authors.forename: Véronique
authors.initials: V
authors.lastname: Mayeux
authors.forename: Denis
authors.initials: D
authors.lastname: Greuet
authors.forename: Jean
authors.initials: J
authors.lastname: Valmier
authors.forename: Frédérique
authors.initials: F
authors.lastname: Scamps
mesh_terms: D000818:Animals; D019771:Axotomy; D020013:Calcium Signaling / Q000502:physiology*; D048429:Cell Size / Q000502:physiology; D002478:Cells, Cultured; D018118:Chloride Channels / Q000096:biosynthesis*; D004594:Electrophysiology; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism*; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D009416:Nerve Regeneration / Q000502:physiology; D016501:Neurites / Q000502:physiology; D009474:Neurons / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D012584:Sciatic Nerve / Q000502:physiology; D015854:Up-Regulation
chemical_list: D018118:Chloride Channels