Figure 3: Continuous endothelial cell and tight junction protein disruption after recombinant MAP4K4 delivery and MAP4K4 silencing post SAH (Experiment III). Endothelium and tight junction discontinuity was demonstrated by lectin and claudin 5 staining in the ipsilateral cortex after MAP4K4 recombinant protein infusion and MAP4K4 siRNA pretreatment, at 24 hours post SAH, under a fluorescence microscope. n = 3. Scale bar: 20 μm. Endothelium and tight junction discontinuity was greater in the SAH group than in the sham group. MAP4K4 increased endothelium and tight junction discontinuity while MAP4K4 siRNA reversed those trends. Arrows indicate discontinuity of endothelial cells and claudin 5. Red: claudin 5; green: lectin; blue: DAPI. DAPI: 4′,6-diamidino-2-phenylindole; MAP4K4: sterile-20-like mitogen-activated protein kinase kinase kinase kinase 4; SAH: subarachnoid hemorrhage; Scr: scramble.