title: [5-HT descending expressing in the dorsal horn of cat spinal cord after deafferentation].
abstract: OBJECTIVE
  To investigate the Serotonin (5-HT) expression in dorsal horn of cat spinal cord and the atypical complex terminal (ACT) after complete dorsal rhizotomy.
  
  
  METHODS
  Ten male adult cats were divided into 2 groups after carrying out the complete dorsal rhizotomy: acute group, which survived 2 weeks; chronic group, which survived 2 months. At maturity, all cats were perfused after anaesthesia, the L6 segments of the spinal cord were removed and prepared for light and electron microscopy of 5-HT immunohistochemistry for observing of ACT.
  
  
  RESULTS
  5-HT immuno-reactivity was demonstrated in dorsal horn especially in laminal II both in operation and control sides in acute group. In chronic group, the 5-HT positive stain in operation sides was stronger than that of control sides. The immuno-positive ACTs were founded in the lamina II of chronic operation side beside some 5-HT immuno-positive simple terminals; they were round or ellipse in shape and usually form flat or convex two synapse with two post-compounds. ACTs mainly contain clear or dense core vesicles.
  
  
  CONCLUSIONS
  The descending 5-HT express in operation side after complete dorsal rhizotomy is mainly on the in lamina II. The 5-HT immuno-positive ACT may imply the mechanism of descending spinal cord plasticity.
authors.affiliation: Department of Anatomy and Histology & Embryology, Chengdu Medical College, Chengdu, China.
authors.forename: Jian-jun
authors.initials: JJ
authors.lastname: Chen
authors.forename: Qin
authors.initials: Q
authors.lastname: Yang
authors.forename: Xin-zhi
authors.initials: XZ
authors.lastname: Li
mesh_terms: D000818:Animals; D002415:Cats; D004525:Efferent Pathways / Q000378:metabolism; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology*; D020671:Posterior Horn Cells / Q000378:metabolism*; D019051:Rhizotomy; D012701:Serotonin / Q000096:biosynthesis* / Q000235:genetics; D013126:Spinal Nerve Roots / Q000601:surgery*
chemical_list: D012701:Serotonin