EDHF, which is not NO, is a major endothelium-dependent vasodilator in mice

Endothelial control of vascular tone is mediated mainly by nitric oxide and the endo­ thelium-derived hyperpolarizing factor (EDHF) . The properties of E D H F and the contri­ bution of E D H F to endothelium-dependent relaxation were determined by studying vasodilator responses to endothelial agonists in wild-type and endothelial N O synthase knockout mice (eNOS - / - ) .