title: Vesicular glutamate transporter-3 contributes to visceral hyperalgesia induced by Trichinella spiralis infection in rats.
abstract: BACKGROUND
  According to a recent study, vesicular glutamate transporter-3 (VGLUT3) contributes to injury-induced mechanical hyperalgesia in mice.
  
  
  OBJECTIVE
  The aims of the study were to investigate whether VGLUT3 is involved in visceral pain, and whether transient intestinal infection or acute cold restraint stress (ACRS) affects VGLUT3 expression levels in rats.
  
  
  METHODS
  Changes in VGLUT3 and c-Fos proteins were evaluated in rats which received noxious colorectal distension (CRD) stimulation. Transient intestinal infection was effected by oral administration of Trichinella spiralis (T. spiralis) larvae in Brown Norway rats. On the 100th day post-infection (PI), half of the PI-rats and non infected controls were subjected to an ACRS procedure. The visceromotor response to CRD was measured using the abdominal withdrawal reflex (AWR) score. Immunofluorescence and western blot analysis were used to estimate the expression of VGLUT3 in both peripheral and central neurons.
  
  
  RESULTS
  Noxious stimulation induced a significant increase in the expression of VGLUT3 in the L6S1 spinal dorsal horn. Compared with the control group, the pain threshold was significantly decreased in the ACRS, PI, and PI + ACRS groups. VGLUT3 expression in the L6S1 dorsal root ganglion (DRG) and spinal neurons were significantly increased in PI and PI + ACRS groups as compared with the control group.
  
  
  CONCLUSIONS
  VGLUT3 is involved in conduction of visceral pain sensation and in visceral hyperalgesia induced by Trichinella spiralis infection in rats.
authors.affiliation: Department of Gastroenterology, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing 100191, China. yangchangqing111@sohu.com
authors.forename: Chang-Qing
authors.initials: CQ
authors.lastname: Yang
authors.forename: Yan-Yu
authors.initials: YY
authors.lastname: Wei
authors.forename: Yu-Xin
authors.initials: YX
authors.lastname: Leng
authors.forename: Chan-Juan
authors.initials: CJ
authors.lastname: Zhong
authors.forename: Yong-Shen
authors.initials: YS
authors.lastname: Zhang
authors.forename: You
authors.initials: Y
authors.lastname: Wan
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Duan
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003106:Colon / Q000503:physiopathology; D004108:Dilatation, Pathologic; D006930:Hyperalgesia / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D007150:Immunohistochemistry; D008297:Male; D017288:Pain Threshold; D020671:Posterior Horn Cells / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D051381:Rats; D011914:Rats, Inbred BN; D012020:Reflex, Abdominal; D013116:Spinal Cord / Q000378:metabolism; D017160:Trichinella spiralis; D014235:Trichinellosis / Q000150:complications*; D050496:Vesicular Glutamate Transport Proteins / Q000378:metabolism* / Q000502:physiology; D059265:Visceral Pain / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology
chemical_list: D016760:Proto-Oncogene Proteins c-fos; C482103:Slc17a8 protein, rat; D050496:Vesicular Glutamate Transport Proteins