Argon Inhalation for 24 Hours After Onset of Permanent Focal Cerebral Ischemia in Rats Provides Neuroprotection and Improves Neurologic Outcome. Issue 8 (August 2019)

• Record Type: Journal Article
• Authors: Ma, Shuang; Chu, Dongmei; Li, Litao; Creed, Jennifer A.; Ryang, Yu-Mi; Sheng, Huaxin; Yang, Wei; Warner, David S.; Turner, Dennis A.; Hoffmann, Ulrike
• Is Part Of: Critical care medicine. Volume 47:Issue 8(2019)
• Publication Date: 2019-08
• Subjects: argon -- neuroprotection -- noble gases -- permanent cerebral ischemia -- rats; Critical care medicine -- Periodicals; Soins intensifs -- Périodiques; 616.028
• DOI: 10.1097/CCM.0000000000003809
• Languages: English
• ISSNs: 0090-3493

Abstract

Abstract : Objectives: We tested the hypothesis that prolonged inhalation of 70% argon for 24 hours after in vivo permanent or temporary stroke provides neuroprotection and improves neurologic outcome and overall recovery after 7 days. Design: Controlled, randomized, double-blinded laboratory study. Setting: Animal research laboratories. Subjects: Adult Wistar male rats ( n = 110). Interventions: Rats were subjected to permanent or temporary focal cerebral ischemia via middle cerebral artery occlusion, followed by inhalation of 70% argon or nitrogen in 30% oxygen for 24 hours. On postoperative day 7, a 48-point neuroscore and histologic lesion size were assessed. Measurements and Main Results: After argon inhalation for 24 hours immediately following "severe permanent ischemia" induction, neurologic outcome (neuroscore, p = 0.034), overall recovery (body weight, p = 0.02), and infarct volume (total infarct volume, p = 0.0001; cortical infarct volume, p = 0.0003; subcortical infarct volume, p = 0.0001) were significantly improved. When 24-hour argon treatment was delayed for 2 hours after permanent stroke induction or until after postischemic reperfusion treatment, neurologic outcomes remained significantly improved (neuroscore, p = 0.043 and p = 0.014, respectively), as was overall recovery (body weight, p = 0.015), compared with nitrogen treatment. However, infarct volume and 7-day mortality were not significantly reduced when argon treatment was delayed. Conclusions: Neurologic outcome (neuroscore), overall recovery (body weight), and infarct volumes were significantly improved after 24-hour inhalation of 70% argon administered immediately after severe permanent stroke induction. Neurologic outcome and overall recovery were also significantly improved even when argon treatment was delayed for 2 hours or until after reperfusion. Abstract : Supplemental Digital Content is available in the text.