title: Effects of intrathecal bupivacaine in conjunction with hypothermia on neuronal protection against transient spinal cord ischemia in rats.
abstract: BACKGROUND
  Excitotoxic neuronal injury from ischemia may be reduced by local anesthetics. We investigated the neuroprotective effects of intrathecally administered bupivacaine and hypothermia in a rat model of transient spinal cord ischemia.
  
  
  METHODS
  PE-10 intrathecal catheter-implanted male Sprague-Dawley rats were randomly assigned to one of four groups: normothermia (NT) and hypothermia (HT) groups (given 15 microl of normal saline) and bupivacaine (B) and bupivacaine-hypothermia (BHT) groups (given 15 mul of 0.5% bupivacaine). Transient spinal cord ischemia was induced by inflation of a 2F Fogarty catheter placed in the aortic arch for 12 min. The rectal temperature was maintained at 37.0 +/- 0.5 degrees C for the NT and B groups, and at 34.5 +/- 0.5 degrees C for the HT and BHT groups. Motor and sensory deficit scores were assessed 2 and 24 h after reperfusion. Lumbar spinal cords were harvested for histopathology and immunoreactivity of heat shock protein 70 (HSP70).
  
  
  RESULTS
  After reperfusion, the motor and sensory deficit scores of the NT group were significantly higher than those of the HT (P < 0.05) and BHT (P < 0.001) groups. Significant differences were evident in the motor and sensory deficit scores between the HT and BHT groups at 24 h (P < 0.05). Neuronal cell death and immunoreactivity of HSP70 were frequently observed in the NT and BT groups, but not in the HT and BHT groups.
  
  
  CONCLUSIONS
  These results collectively suggest that intrathecal bupivacaine does not provide neuroprotection during normothermic transient spinal cord ischemia in rats, but enhances the neuroprotective effects of hypothermia.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Inje University, College of Medicine, Ilsan, South Korea.
authors.forename: J-R
authors.initials: JR
authors.lastname: Lee
authors.forename: S-M
authors.initials: SM
authors.lastname: Han
authors.forename: J-G
authors.initials: JG
authors.lastname: Leem
authors.forename: S-J
authors.initials: SJ
authors.lastname: Hwang
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage*; D000818:Animals; D001794:Blood Pressure; D002045:Bupivacaine / Q000008:administration & dosage*; D007036:Hypothermia, Induced; D007278:Injections, Spinal; D008297:Male; D009460:Neurologic Examination; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000473:pathology; D020760:Spinal Cord Ischemia / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*
chemical_list: D000779:Anesthetics, Local; D002045:Bupivacaine