title: Normal nerve striations are altered in the trembler-J mouse, a model of Charcot-Marie-Tooth disease.
abstract: BACKGROUND
  This study was initiated because it was noted that the peripheral nerves of Trembler-J mice (a model of human Charcot-Marie-Tooth disease) appear to lack normal striations.
  
  
  METHODS
  We performed confocal microscopy of whole sciatic nerves and tested the effect of axial stress on impulse conduction.
  
  
  RESULTS
  We found that the axons of mutant mice were longer than those of the wild-type (1.55 mm of axon/mm length of nerve vs. 1.28 mm/mm respectively). This axonal elongation altered the helical nerve striations (bands of Fontana). As nerves were stretched axially, the conduction distance became correspondingly shorter. The effect on latency was significantly greater in the more coiled nerves of Trembler-J mice (P = 0.038).
  
  
  CONCLUSIONS
  The finding that mice with a mutated peripheral myelin protein 22 (PMP22) possess excessively long axons may be related to the excess Schwann cell numbers found in this disorder.
authors.affiliation: School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Bridget J
authors.initials: BJ
authors.lastname: Power
authors.forename: Gavin
authors.initials: G
authors.lastname: O'reilly
authors.forename: Robert
authors.initials: R
authors.lastname: Murphy
authors.forename: Keith J
authors.initials: KJ
authors.lastname: Murphy
authors.forename: Mark
authors.initials: M
authors.lastname: Pickering
authors.forename: James F X
authors.initials: JF
authors.lastname: Jones
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001369:Axons / Q000473:pathology; D002607:Charcot-Marie-Tooth Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D004195:Disease Models, Animal; D004594:Electrophysiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008818:Mice, Neurologic Mutants; D018613:Microscopy, Confocal; D009154:Mutation / Q000235:genetics; D009185:Myelin Proteins / Q000235:genetics; D009186:Myelin Sheath / Q000378:metabolism / Q000473:pathology; D009431:Neural Conduction / Q000235:genetics / Q000502:physiology*; D012584:Sciatic Nerve / Q000378:metabolism / Q000503:physiopathology*; D013314:Stress, Mechanical
chemical_list: D009185:Myelin Proteins; C489545:Pmp22 protein, mouse
keywords: Charcot-Marie-Tooth disease; bands of Fontana; nerve stretch; rat; sciatic nerve