NOS3 and endothelial dysfunction: In vitro incubation with calcitriol was observed to prevent EMP formation from endothelial cells exposed to increased oxidative stress, probably through an increase in eNOS expression and inhibition of Rho-associated coiled-coil protein kinase 1, a key regulator of actin–myosin contraction, which appears to be abnormally expressed in patients with endothelial dysfunction and CVD [36].