title: Changes of 5-hydroxytryptamine and tryptophan hydroxylase expression in the ventral horn of spinal cord.
abstract: OBJECTIVE
  To investigate changes of 5-hydroxytryptamine (5-HT) and its synthesis rate-limiting enzyme tryptophan hydroxylase (TPH) in the ventral horn of spinal cord after exercise-induced fatigue, and to further discuss the mechanism of exercise-induced central fatigue at spinal level.
  
  
  METHODS
  Sixteen healthy adult Wistar rats were randomly divided into 2 groups: exercise-induced fatigue group and control group. Immunohistochemical staining for 5-HT and TPH in the ventral horn were performed and analyzed quantitatively. The mean optic densities of 5-HT and TPH positive fibers or terminals were measured by computerized image analyzer.
  
  
  RESULTS
  Both 5-HT and TPH positive fibers/terminals decreased in the exercise-induced fatigue group. The immunohistochemical staining was weaker and the mean optic densities decreased obviously in the fatigue group compared with those in the control group (P< 0.05).
  
  
  CONCLUSIONS
  5-HT and TPH in the ventral horn of spinal cord might be involved in exercise-induced fatigue.
authors.affiliation: Institute of Healthy and Environmental Medicine, Academy of Military Medical Sciences, Tianjin 300050, China.
authors.forename: Chuan-Xiang
authors.initials: CX
authors.lastname: Xu
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: Liu
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
mesh_terms: D000818:Animals; D005221:Fatigue / Q000378:metabolism*; D008297:Male; D009043:Motor Activity; D009474:Neurons / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D066151:Spinal Cord Ventral Horn / Q000201:enzymology / Q000378:metabolism*; D014365:Tryptophan Hydroxylase / Q000378:metabolism*
chemical_list: D012701:Serotonin; D014365:Tryptophan Hydroxylase