title: Unpredictability of triphenyltetrazolium chloride in staining irreversible ischaemia-reperfusion injury in the skeletal muscle of rats.
abstract: OBJECTIVE
  To find out whether pale staining with triphenyltetrazolium chloride (TTC) in skeletal muscle of rat hindlimbs which had been subjected to ischaemia-reperfusion definitely indicated irreversible tissue damage.
  
  
  METHODS
  Laboratory study.
  
  
  METHODS
  University hospital, Taiwan.
  
  
  METHODS
  77 Female Wistar rats.
  
  
  METHODS
  Ischaemia of one hindlimb was caused by wrapping of a tourniquet above knee joint for 1.5 (n = 14). 2 (n = 15), 2.5 (n = 17), 3 (n = 17) or 4 (n = 14) hours. Each ischaemic group was divided into three subgroups to receive nil, 1 or 1.5 hours reperfusion, respectively. Gastrocnemius and soleus muscles were excised bilaterally.
  
  
  METHODS
  TTC reduction in the ischaemic limbs presented as a percentage of the opposite control limb measured by a spectrophotometric assay. Density of red formazan deposition in the ischaemic limbs assessed by microscopic examination of the TTC histochemical stain in the 3 hour ischaemic group.
  
  
  RESULTS
  In the 2, 2.5, and 3 hour ischaemic groups the TTC reduction in the ischaemic limbs after 1.5 hours reperfusion increased significantly as compared with that with one hour reperfusion (p < 0.01 in each case). The density of red formazan deposition in the muscle after 3 hours ischaemia and 1.5 hours reperfusion was significantly higher than that of only 1 hour of reperfusion.
  
  
  CONCLUSIONS
  Lack of TTC staining does not necessarily represent irreversible ischaemia-reperfusion injury of the skeletal muscle in rats.
authors.affiliation: Department of Emergency Medicine and Surgery, College of Medicine, National Taiwan University, Taipei.
authors.forename: H T
authors.initials: HT
authors.lastname: Cheng
authors.forename: H
authors.initials: H
authors.lastname: Chang
authors.forename: H J
authors.initials: HJ
authors.lastname: Lue
authors.forename: C Y
authors.initials: CY
authors.lastname: Wen
mesh_terms: D000818:Animals; D004396:Coloring Agents; D005260:Female; D006614:Hindlimb / Q000098:blood supply; D007511:Ischemia / Q000473:pathology*; D018485:Muscle Fibers, Skeletal / Q000473:pathology; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000473:pathology; D009336:Necrosis; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000473:pathology*; D013778:Tetrazolium Salts
chemical_list: D004396:Coloring Agents; D013778:Tetrazolium Salts; C009591:triphenyltetrazolium