title: Unchanged c-Fos expression after extracorporeal shock wave therapy: an experimental investigation in rats.
abstract: BACKGROUND
  Despite the extensive use of extracorporeal shock wave therapy (ESWT) in the therapy of chronic tendopathies, the biological mechanisms of its antinociceptive effects are still unclear.
  
  
  METHODS
  In this study we addressed the question of whether the clinically described, long-lasting effect of ESWT is mediated by changes in the activity of spinal cord neurones. As a marker for neuronal activity which is also able to interfere with the molecular expression pattern of neurones, the expression of the inducible transcription factor c-Fos was analysed in the animal model of the rat. Despite application of different energy levels, the analysis of c-Fos protein expression at an early (4 h) and late (72 h) time point after ESWT revealed no visible changes in immunoreactivity in the dorsal horn of the spinal cord. Additionally, there was no change in c-Fos protein and its gene expression c-Fos mRNA in the treatment area of the paw.
  
  
  CONCLUSIONS
  We conclude that ESWT with an energy flux dose up to 0.33 mJ/mm(2)does not modify neuronal activity. Since the application of ESWT showed no significant changes in the immunoreactivity of c-Fos, it is therefore unlikely that ESWT triggers stimulation-produced analgesia via activation of peripheral nerves.
authors.affiliation: Department for Orthopaedics and Rheumatology, Philipps-Universität Marburg, Baldingerstrasse 1, 35043 Marburg, Germany. haake2@mailer.uni-marburg.de
authors.forename: Michael
authors.initials: M
authors.lastname: Haake
authors.forename: Alexander
authors.initials: A
authors.lastname: Thon
authors.forename: Michael
authors.initials: M
authors.lastname: Bette
mesh_terms: D000818:Animals; D019220:High-Energy Shock Waves / Q000627:therapeutic use*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D023421:Models, Animal; D009474:Neurons / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D013116:Spinal Cord / Q000166:cytology
chemical_list: D016760:Proto-Oncogene Proteins c-fos