EDN1 and Hypertension: 2006; Fujita et al. 2006; Eggleston et al. 2007), whereas others demonstrate either null effect or reduction in blood flow in lean, healthy individuals (Hedman et al. 2001; Arcaro et al. 2002; Morgantini et al. 2012). Insulin infusion in rats has been shown to increase plasma ET‐1 and precipitate hypertension (Juan et al. 2004; Potenza et al. 2005). Similarly, in vitro studies have consistently demonstrated increased ET‐1 gene expression in insulin‐treated endothelial cells (Formoso et al. 2006; Yang and Li 2008).