title: Changes of calcitonin gene-related peptide in primary sensory neurons and their central branch after nerve root compression of the dog.
abstract: OBJECTIVE
  To investigate changes in axonal flow after nerve root compression by using immunohistochemical techniques to detect calcitonin gene-related peptide (CGRP), which is thought to be involved in pain sensation.
  
  
  METHODS
  Experimental, controlled study.
  
  
  METHODS
  University medical school in Japan.
  
  
  METHODS
  Forty adult mongrel dogs (weight, 7-15kg).
  
  
  METHODS
  In dogs, the lumbar nerve roots were compressed using 4 types of clips with different pressures. Changes of CGRP levels in the spinal dorsal horn, dorsal root, and dorsal root ganglia (DRG) were examined immunohistochemically after compression for 24 hours or for 1 week.
  
  
  METHODS
  CGRP-positive neurons and CGRP-positive fibers.
  
  
  RESULTS
  After compression, axonal flow in the dorsal root was impaired, accumulation of CGRP was observed distal to the site of compression, and the number of DRG cells showing positively for CGRP decreased. Compression for 1 week resulted in a decrease in the number of CGRP-positive fibers in the spinal dorsal horn.
  
  
  CONCLUSIONS
  These findings indicate that CGRP dynamics are modified by nerve compression.
authors.affiliation: Department of Rehabilitation Medicine, Fukui University School of Medicine, Matsuoka, Fukui, Japan. kshigeru@fmsrsa.fukui-med.ac.jp
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sasaki
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Shimada
authors.forename: Makoto
authors.initials: M
authors.lastname: Kaneyasu
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Mizukami
authors.forename: Ippei
authors.initials: I
authors.lastname: Kitade
authors.forename: Mayumi
authors.initials: M
authors.lastname: Ogawa
authors.forename: Hideo
authors.initials: H
authors.lastname: Kawahara
authors.forename: Hisatoshi
authors.initials: H
authors.lastname: Baba
authors.forename: Hidezo
authors.initials: H
authors.lastname: Yoshizawa
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000502:physiology*; D004285:Dogs; D005727:Ganglia, Spinal / Q000473:pathology; D009475:Neurons, Afferent / Q000473:pathology*; D011843:Radiculopathy / Q000473:pathology*
chemical_list: D015740:Calcitonin Gene-Related Peptide