title: Induction of intervertebral disc cell apoptosis and degeneration by chronic unpredictable stress.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effects of chronic unpredictable stress on the intervertebral discs of rats.
  
  
  METHODS
  The cellular events involved in injury- and stress-induced disc degeneration were investigated in male Wistar rats. Disc degeneration and apoptosis were evaluated using microscopic (light and electron) and molecular (immunoblotting and immunohistochemistry) methods. Corticosterone levels were used as markers of stress and measured by radioimmunoassay.
  
  
  RESULTS
  The data gathered in this study showed that chronic unpredictable stress can significantly increase corticosterone levels. Furthermore, biochemical markers of apoptosis (that is, increases in the Bax/Bcl2 ratio and TUNEL reactivity [p < 0.05]) were observed in the stressed animals. Electron and light microscopy also showed disc degeneration and apoptotic cells in the experimental groups.
  
  
  CONCLUSIONS
  Taken together, these data demonstrated that chronic stress is most likely to be a risk factor for creating intervertebral disc degeneration and that programmed cell death may be one of the mechanisms of stress-induced disc degeneration.
authors.affiliation: Departments of Neurosurgery and.
authors.forename: Hamed Reihani
authors.initials: HR
authors.lastname: Kermani
authors.forename: Hamid
authors.initials: H
authors.lastname: Hoboubati
authors.forename: Saeed
authors.initials: S
authors.lastname: Esmaeili-Mahani
authors.forename: Majid
authors.initials: M
authors.lastname: Asadi-Shekaari
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D003345:Corticosterone / Q000097:blood; D004195:Disease Models, Animal; D020287:In Situ Nick-End Labeling; D055959:Intervertebral Disc Degeneration / Q000503:physiopathology*; D008297:Male; D008854:Microscopy, Electron; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D013314:Stress, Mechanical; D051028:bcl-2-Associated X Protein / Q000097:blood; D051025:bcl-Associated Death Protein / Q000097:blood
chemical_list: C494821:Bad protein, rat; C494828:Bax protein, rat; D051028:bcl-2-Associated X Protein; D051025:bcl-Associated Death Protein; D003345:Corticosterone