Fig. 1.

Ischemic tolerance

(A) Brain tissues exposed to invasive ischemia (Lethal ischemia) develop severe neuronal damage and cell death (white area surrounded by dotted line). (B) If the brain experiences mild non-invasive ischemia as preconditioning (PC) prior to invasive ischemia, the damage induced by lethal ischemia is significantly reduced. This is termed ischemic tolerance. (C) PC that induces ischemic tolerance does not necessarily have to be ischemia; stimuli that mimic bacterial infection such as LPS, heat, physical stimuli, or chemicals can also induce ischemic tolerance. This is termed cross-tolerance or remote-tolerance