title: Posttraumatic Chondrocyte Apoptosis in the Murine Xiphoid.
abstract: OBJECTIVE
  To demonstrate posttraumatic chondrocyte apoptosis in the murine xiphoid after a crush-type injury and to ultimately determine the pathway (i.e., intrinsic or extrinsic) by which chondrocytes undergo apoptosis in response to mechanical injury.
  
  
  METHODS
  The xiphoids of adult female wild-type mice were injured with the use of a modified Kelly clamp. Postinjury xiphoid cartilage was analyzed via 3 well-described independent means of assessing apoptosis in chondrocytes: hematoxylin and eosin staining, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, and activated caspase-3 staining.
  
  
  RESULTS
  Injured specimens contained many chondrocytes with evidence of apoptosis, which is characterized by cell shrinkage, chromatin condensation, nuclear fragmentation, and the liberation of apoptotic bodies. There was a statistically significant increase in the number of chondrocytes undergoing apoptosis in the injured specimens as compared with the uninjured specimens.
  
  
  CONCLUSIONS
  Chondrocytes can be stimulated to undergo apoptosis as a result of mechanical injury. These experiments involving predominantly cartilaginous murine xiphoid in vivo establish a baseline for future investigations that employ the genetic and therapeutic modulation of chondrocyte apoptosis in response to mechanical injury.
authors.affiliation: Department of Anesthesiology, Washington University, St Louis, MO, USA.
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Davis
authors.affiliation: Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Eisner
authors.affiliation: Department of Anesthesiology, Washington University, St Louis, MO, USA.
authors.forename: Margaret
authors.initials: M
authors.lastname: McGlynn
authors.affiliation: Department of Internal Medicine, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Shelton
authors.affiliation: Department of Pathology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
authors.forename: James
authors.initials: J
authors.lastname: Richardson
authors.affiliation: Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA ; Texas Health Physicians Group, Arlington, TX, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Borrelli
authors.affiliation: Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
authors.forename: Christopher C T
authors.initials: CC
authors.lastname: Chen
keywords: apoptosis; chondrocytes; injury; murine; xiphoid