title: [An experimental study on large fragment deletion of rat myocardial mitochondrial DNA during early postburn stage].
abstract: OBJECTIVE
  To investigate the influence of peroxidative injury in rat myocardium on the mitochondrial DNA (mtDNA) during early postburn stage.
  
  
  METHODS
  Thirty-six Sprague-Dawley (SD) rats were employed in the study and were randomly divided into sham scald (SS) and scald groups. The rats in scald groups were inflicted with 30% TBSA III degree scalding and were further divided into 1, 3, 6, 12 and 24 post-scald hour (PSH) groups. The mtDNA deletion was determined by semi-quantitative PCR. The rat myocardial tissue samples were harvested and homogenized and the contents of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined.
  
  
  RESULTS
  There was no mtDNA deletion in the rat myocardium in SS group. Partial or complete large fragment (4.8 kb) mtDNA deletion in the rat myocardium was identified at 1, 3 and 24 PSHs (P < 0.05 or 0.01). The SOD activity in the rat myocardium significantly decreased at 1 PSH, reaching the lowest level (76.90 +/- 8.30 U/mg) at 6 PSH, but the MDA content increased evidently at 1 PSH, peaking [(3.17 +/- 0.80) nmol/mg] at 6 PSH (P < 0.05).
  
  
  CONCLUSIONS
  Peroxidative injury to the rat myocardium during early postburn stage might be the principal cause of the 4834 bp deletion of mtDNA in rat myocardium.
authors.affiliation: Institute of Burn Research, Southwest Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, The Third Military Medical University, Chongqing 400038, P.R. China.
authors.forename: Dong-xia
authors.initials: DX
authors.lastname: Zhang
authors.forename: Yue-sheng
authors.initials: YS
authors.lastname: Huang
authors.forename: Song-tao
authors.initials: ST
authors.lastname: Zhao
authors.forename: Xiao-dong
authors.initials: XD
authors.lastname: Li
mesh_terms: D000818:Animals; D002056:Burns / Q000235:genetics / Q000378:metabolism*; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008929:Mitochondria, Heart / Q000235:genetics* / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors
chemical_list: D004272:DNA, Mitochondrial; D008315:Malondialdehyde; D013482:Superoxide Dismutase