In terms of vasoconstrictors, blocking endothelin-1 receptors during rhythmic handgrip exercise has been shown to enhance muscle BF responses in T2D patients but not in healthy controls, indicating augmented endothelin 1-mediated vasoconstriction during exercise in T2D (Schreuder et al., 2014). The gene discussed is EDN1; the disease is type 2 diabetes mellitus.