title: [Mechanism of radiculopathy induced by experimentally herniated nucleus pulposus in rats].
abstract: OBJECTIVE
  To determine the effects of the autologous nucleus pulposus on the pain-related behaviors of hind paws in rats.
  
  
  METHODS
  The nucleus pulposus harvested from autologous coccygeal vertebra was applied beside the unilateral L4 and L5 nerve roots without compression. The mechanical withdrawal threshold of both paws were measured in different times after surgery. And hematoxylin and eosin (HE) staining was applied to observe the changes of nucleus pulposus and nerve roots.
  
  
  RESULTS
  Mechanical sensitivity of the operated side in paws obviously increased after application of autologous nucleus pulposus beside the lumbar nerve roots without compression. And HE staining showed obviously inflammatory changes in the nucleus pulposus and vacuolation in the nerve roots.
  
  
  CONCLUSIONS
  Inflammation resulted from nucleus pulposus may contribute to the development of mechanical hyperalgesia. The results suggest that in addition to mechanical compression, inflammation may be an important factor in the pathogenesis of sciatica.
authors.affiliation: Institute of Orthopedics, 304 Hospital of People's Liberation Army, Beijing 100037, China.
authors.forename: Jia-guang
authors.initials: JG
authors.lastname: Tang
authors.forename: Shu-xun
authors.initials: SX
authors.lastname: Hou
authors.forename: Wei-jia
authors.initials: WJ
authors.lastname: Zhang
authors.forename: Hong-ying
authors.initials: HY
authors.lastname: Liang
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006930:Hyperalgesia / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D011843:Radiculopathy / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley