Cerebral protection by hypoxic preconditioning in a murine model of focal ischemia-reperfusion

Sublethal periods of hypoxia or ischemia can induce adaptive mechanisms to protect against subsequent lethal ischemic insults in a process known as ischemic preconditioning. In the present study, we developed a murine model of cerebral preconditioning using several common strains of adult mice. Animals were exposed to sublethal hypoxia (11% oxygen for 2 h) 48 h prior to a 90 min period of transient focal middle cerebral artery occlusion, induced by an intraluminal filament; injury was assessed 24 h later by TTC staining. Infarct volume in hypoxia-preconditioned animals was reduced 46%, 58%, and 64% in C57B1/6, 129SvEv, and Swiss-Webster ND4 mice relative to their respective untreated controls. This noninvasive murine model of ischemic tolerance should be useful for elucidating the molecular basis of this protection using transgenic and knockout mice. NeuroReport 12:1663-1669 (C) 2001 Lippincott Williams & Wilkins.