The central mechanism of endothelial dysfunction is impaired basal andstimulated formation of nitric oxide, a powerful vasodilator, inhibitor ofplatelet and leukocyte aggregation, and anti-inflammatory agent [93].Dysregulation of endothelial nitric oxide synthase (eNOS) likely contributes toendothelial dysfunction in PTSD. Here, NOS3 is linked to post-traumatic stress disorder.