“…The structural and functional integrity of endothelial cells is essential for maintaining stable cerebral autoregulation ( Preckel et al, 1996 ; White et al, 2000 ; Ainslie et al, 2007 ; Guo et al, 2016 ). After SAH, both structural and functional integrity were damaged because of factors, such as the high concentration of ROS/RNS and inflammatory responses ( Figure 1 ) ( Kajita et al, 1998 ; Scharbrodt et al, 2009 ; Szatmari et al, 2010 ; Sabri et al, 2011 ; Qin et al, 2012 ; Liu et al, 2016 ; de Azevedo et al, 2017 ; Shekhar et al, 2017 ; Armstead et al, 2018 ). In inflammatory responses, various inflammatory pathways, such as the NF-κB pathway ( Pawlowska et al, 2018 ), NLRP3 pathway ( Li et al, 2016 ; Shao et al, 2016 ), and TLR4 pathway ( Zhang et al, 2016 ), are activated and have negative effects on the arterial endothelium after SAH.…”