title: Apoptosis in the sequestrated nucleus pulposus compared to the remaining nucleus pulposus in the same patient.
abstract: METHODS
  Both sequestrated nucleus pulposus (SNP) and the remaining nucleus pulposus (RNP) were studied from the discs of the same patient to evaluate apoptosis using immunohistochemical staining.
  
  
  OBJECTIVE
  To compare apoptosis of the SNP and the RNP in the disc of the same patient.
  
  
  BACKGROUND
  Many studies have been conducted on the natural history and apoptosis of the herniated nucleus pulposus; however, apoptosis of the remaining nucleus cells, after removal of the sequestrated disc, in the same patient, has not been reported.
  
  
  METHODS
  Eight samples of SNP and RNP from the disc of the same patient were obtained. The TUNEL stain was performed to confirm the occurrence of apoptosis in disc cells. Immunohistochemistry staining and Western blot analysis were performed to determine the presence of proteins, including caspase-3,-8,-9, and Bid.
  
  
  RESULTS
  TUNEL-positive chondrocytes were identified in all of the SNP and RNP samples; the apoptotic index was 5.8 ± 1.9% and 5.9 ± 1.2%, respectively (P = 0.60). Caspase-3,-8,-9, and Bid were expressed in the SNP and the RNP of the cytoplasm and the nucleus by the immunohistochemical staining. The expression of active caspase-3,-8,-9, and Bid in the RNP of the disc and the SNP was different in each patient.
  
  
  CONCLUSIONS
  The frequency of chondrocyte apoptosis in the SNP and the RNP was not different in the disc. The pathways involved in chondrocyte apoptosis of the SNP and the RNP differed among individuals and included intrinsic and/or extrinsic pathways.
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.
authors.forename: Kee-Yong
authors.initials: KY
authors.lastname: Ha
authors.forename: Bae-Gyun
authors.initials: BG
authors.lastname: Kim
authors.forename: Ki-Won
authors.initials: KW
authors.lastname: Kim
authors.forename: In-Soo
authors.initials: IS
authors.lastname: Oh
authors.forename: Jun-Yeong
authors.initials: JY
authors.lastname: Seo
mesh_terms: D000328:Adult; D017209:Apoptosis; D051023:BH3 Interacting Domain Death Agonist Protein / Q000378:metabolism; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D019902:Chondrocytes / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D007403:Intervertebral Disc / Q000378:metabolism / Q000473:pathology*; D007405:Intervertebral Disc Displacement / Q000378:metabolism / Q000473:pathology*; D008159:Lumbar Vertebrae / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D051023:BH3 Interacting Domain Death Agonist Protein; C494814:BID protein, human; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9