Moreover, retinal ganglion cells (RGCs) also control retinal vessel growth through G protein-coupled receptor-91 (GPR91) (Sapieha et al., 2008) and neuronal guidance cue semaphorin 3 A (SEMA3A) (Joyal et al., 2011), and capillary degeneration in mice induced with ischemia-reperfusion injury (Ueda et al., 2010; Zheng et al., 2007). Here, SUCNR1 is linked to ischemia reperfusion injury.