title: Plasticity of dorsal root ganglion neurons in a rat model of post-infectious gut dysfunction: potential implication of nerve growth factor.
abstract: OBJECTIVE
  Intestinal infections are suggested as a risk factor for the development of irritable bowel syndrome (IBS)-like visceral hypersensitivity. The mechanisms implicated might involve long-term changes in visceral afferents, with implication of nerve growth factor (NGF). We explored plastic changes in dorsal root ganglia (DRGs) receiving innervation from the gut and the potential implication of NGF in a rat model of IBS-like post-infectious gut dysfunction.
  
  
  METHODS
  Rats were infected with Trichinella spiralis larvae. Thirty days post-infection, inflammatory markers, including interleukins (ILs) and mucosal mast cell infiltration (rat mast cell protease II [RMCPII]), and NGF and TrkA expression was determined in the jejunum and colon (RT-qPCR). In the same animals, morphometry (neuronal body size) and NGF content (immunofluorescence) were assessed in thoracolumbar DRG neurons.
  
  
  RESULTS
  In infected animals, a low-grade inflammatory-like response, characterized by up-regulated levels of RMCPII and IL-6, was observed in the jejunum and colon. TrkA expression was increased in the jejunum, whereas the colon showed a slight reduction. NGF levels remained unaltered regardless the gut region. Overall, the mean cross-sectional area of DRG neurons was increased in T. spiralis-infected animals, with a reduction in both TrkA and NGF staining.
  
  
  CONCLUSIONS
  Results suggest that during T. spiralis infection in rats, there is a remodeling of sensory afferents that might imply a NGF-mediated mechanism. Plastic changes in sensory afferents might mediate the long-lasting functional alterations that characterize this model of IBS. Similar mechanisms might be operating in patients with post-infectious-IBS.
authors.affiliation: Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona , Barcelona , Spain.
authors.forename: Ferran
authors.initials: F
authors.lastname: Jardí
authors.forename: Joan A
authors.initials: JA
authors.lastname: Fernández-Blanco
authors.forename: Vicente
authors.initials: V
authors.lastname: Martínez
authors.forename: Patri
authors.initials: P
authors.lastname: Vergara
mesh_terms: D000818:Animals; D003092:Colitis / Q000150:complications* / Q000378:metabolism / Q000503:physiopathology; D004195:Disease Models, Animal; D005727:Ganglia, Spinal / Q000503:physiopathology*; D043183:Irritable Bowel Syndrome / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D020932:Nerve Growth Factor / Q000502:physiology*; D009473:Neuronal Plasticity; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D020932:Nerve Growth Factor
keywords: Trichinella spiralis; TrkA receptor; dorsal root ganglion; irritable bowel syndrome; mast cells; nerve growth factor