title: The protective effect of ischemic preconditioning against hepatic ischemic-reperfusion injury under isoflurane anesthesia in rats.
abstract: OBJECTIVE
  Apoptosis is a central mechanism of ischemic-reperfusion injury (IRI) to the liver. Among the methods to reduce IRI, ischemic preconditioning (IP) has been shown to confer protection. Therefore, the aim of this study was to determine if IP conferred protection against hepatic IRI under isoflurane anesthesia in rats and to investigate underlying protective mechanisms.
  
  
  METHODS
  Twenty-three rats weighing 270 to 300 grams were randomly divided into three groups: (1) the sham operated group (n = 5); (2) the non-IP group (n = 9; 45 minutes of hepatic ischemia followed by 2 hours of reperfusion); and (3) the IP group (n = 9); IP induced by 10 minutes of hepatic ischemia followed by 15 minutes of reperfusion before 45 minutes of prolonged hepatic ischemia). Anesthesia was maintained with isoflurane (1.5%). We compared the degrees of hepatic injury and expressions of B cell lymphoma 2 (Bcl-2) and caspase 3 and 8 mRNAs.
  
  
  RESULTS
  The IP group showed significantly lower levels of aspartate transaminase and alanine transaminase as well as reduced histological grades of hepatocyte injury compared with the non-IP group at 2 hours after reperfusion. At the corresponding time, the Bcl-2 mRNA level was 2-fold higher in the IP group. Caspase 3 mRNA levels were highest in the non-IP group significantly compared with the sham cohort. Similarly, caspase 8 mRNA levels were highest in the Non_IP group albeit not significancely.
  
  
  CONCLUSIONS
  IP protected against hepatic IRI under isoflurane anesthesia in rats. The mechanism of protection appeared to involve upregulation of Bcl-2 expression resulting in inhibited apoptosis.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: J S
authors.initials: JS
authors.lastname: Ko
authors.forename: M S
authors.initials: MS
authors.lastname: Gwak
authors.forename: G S
authors.initials: GS
authors.lastname: Kim
authors.forename: Y H
authors.initials: YH
authors.lastname: Shin
authors.forename: S
authors.initials: S
authors.lastname: Ryu
authors.forename: J-S
authors.initials: JS
authors.lastname: Kim
authors.forename: S J
authors.initials: SJ
authors.lastname: Kim
authors.forename: S T
authors.initials: ST
authors.lastname: Kim
mesh_terms: D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D000818:Animals; D019194:Ischemic Preconditioning; D007530:Isoflurane / Q000008:administration & dosage*; D008099:Liver / Q000098:blood supply*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000517:prevention & control*
chemical_list: D018685:Anesthetics, Inhalation; D007530:Isoflurane