title: The effect of heliox treatment in a rat model of focal transient cerebral ischemia.
abstract: Manipulation of inhaled gases during ischemia/reperfusion is a potential novel therapy for acute stroke. We previously found that treatment with a mixture of 70%/30% helium/oxygen (heliox) or 100% oxygen protects the brain against acute focal ischemia-reperfusion injury. This study evaluates the potential neuro-protective effects of delayed heliox treatment and its dose response effects in a rat transient focal cerebral ischemia model. Adult male rats were subjected to 2-h middle cerebral artery occlusion and then assigned to 1 of 4 inhaled gas exposure groups: I: 70%/30% nitrogen/oxygen (control); II: 70%/30% helium/oxygen administered immediately after occlusion; III: 70%/30% helium/oxygen administered after a 30-60 min delay; or, IV: 40%/30%/30% nitrogen/helium/oxygen administered immediately after occlusion. Outcome measurements included infarct size and neurological deficit score. Mean infarct sizes from groups I to IV were 228, 35, 109, and 124 mm³ respectively (p=0.012). Only group II had significantly smaller infarct size compared to the control group (p=0.008). In addition, only Group II had a significantly lower neurological deficit score at 24h post ischemia when compared to the control group (p<0.001). Since heliox reduced infarct size and improved neurological deficit scores if initiated immediately after onset of ischemia, it may be a useful adjuvant to other stroke therapies.
authors.affiliation: Department of Neurology & Psychiatry, Saint Louis University, 1438 S. Grand Boulevard, Saint Louis, MO 63104, USA. pany@slu.edu
authors.forename: Yi
authors.initials: Y
authors.lastname: Pan
authors.forename: Haibo
authors.initials: H
authors.lastname: Zhang
authors.forename: Aninda B
authors.initials: AB
authors.lastname: Acharya
authors.forename: Salvador
authors.initials: S
authors.lastname: Cruz-Flores
authors.forename: W Michael
authors.initials: WM
authors.lastname: Panneton
mesh_terms: D000208:Acute Disease; D000818:Animals; D004195:Disease Models, Animal; D006371:Helium / Q000494:pharmacology*; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology / Q000517:prevention & control / Q000628:therapy*; D002546:Ischemic Attack, Transient / Q000473:pathology / Q000628:therapy*; D008297:Male; D009584:Nitrogen / Q000494:pharmacology; D010100:Oxygen / Q000494:pharmacology*; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
chemical_list: D006371:Helium; C038949:heliox; D009584:Nitrogen; D010100:Oxygen