Subarachnoid hemorrhage (SAH) caused by the rupture of a cerebral aneurysm is a well-known devastating cerebrovascular disease.Post-SAH brain is vulnerable,associated with early brain injury (EBI;Suzuki,2015).The first step for intensive care of aneurysmal SAH patients is aneurysmal obliteration to prevent rebleeding as well as further aggravation of EBI (Suzuki,2015).The subsequent treatment requires intensive medical care to manage the associated problems including hydrocephalus,cerebral vasospasm and delayed cerebral ischemia (DCI).Despite improvements in the clinical management of SAH,DCI remains one of the most important causes of morbidity and mortality in SAH patients who survive the initial bleeding.Recently,EBI as well as cerebral vasospasm is considered to be a cause of DCI (Suzuki,2015).However,the pathogenesis of EBI,cerebral vasospasm and DCI remains unclear,precluding the development of new therapies against them.