Brain ischemia, also known as cerebral ischemia or ischemic stroke, is the third most common cause of death worldwide, after heart attack and cancer, resulting in major negative social and economic consequences. ischemic stroke, which results from cardiac arrest, cerebral arterial occlusion or severe vasospasm after subarachnoid ischemia, causes devastating damage to the brain and represents a serious global health problem. briefly, brain ischemia is a condition in which there is insufficient blood flow to meet metabolic demands. it is known that an interruption of blood flow to the brain for more than 10 seconds results in a loss of consciousness, leading to ischemia and irreversible brain damage. the most common cause of stroke is the sudden occlusion of a blood vessel by a thrombus or embolism, resulting in an almost immediate loss of oxygen and glucose to the cerebral tissue. ischemia can be classified as either focal or global. focal ischemia is confined to a specific lesion, whereas global ischemia encompasses a wide area of the brain (see gusev and skvortsova, 2003). given the clinical importance of ischemia, it is not surprising that its causes, diagnosis and treatment are the focus of a major international research effort (see liebeskind, 2008; slemmer et al., 2008; dogrukol-ak et al., 2009; indraswari et al., 2009; kim et al., 2009; chauveau et al., 2010; gupta et al., 2010; henninger et al., 2010; rymner et al., 2010; cucchiara and kasner, 2011; yenari and hemmen, 2010; fisher, 2011; kunst and schaefer, 2011; leiva- salinas et al., 2011; molina, 2011; ramos-fernandez et al., 2011; turner and adamson, 2011; wechsler, 2011). to provide an idea of the volume of research carried out in this area, a keyword search on may 16th, 2011 using the pubmed national center for biotechnology information (ncbi) search engine revealed 78,103 articles containing the search term ‘brain ischemia’. more specifically, there were 58,357 articles containing both ‘brain ischemia’ and ‘human’, and 28,253 containing both ‘brain ischemia’