INS and endothelial dysfunction: Additional to inhibition of sympathetic drive, Imidazoline 1 agonists have been demonstrated to beneficially influence glucose and lipid metabolism and insulin sensitivity (Haenni and Lithell, 1999; Chazova et al., 2006; Fenton et al., 2006), hemodynamic and neuroendocrine parameters (Mitrovic et al., 1991), endothelial dysfunction (Topal et al., 2006) and inflammatory cytokine production (Pöyhönen-Alho et al., 2008) when used in hypertensive, overweight and insulin resistant subjects.