We recently showed that intradermal administration of endothelin-1 diminished endothelium-dependent and -independent cutaneous vasodilation. We evaluated the hypothesis that Rho kinase may be a mediator of this response. We also sought to evaluate if endothelin-1 increases sweating. In twelve adults (25±6 years), we measured cutaneous vascular conductance (CVC) and sweating during 1) endothelium-dependent vasodilation induced via administration of incremental doses of methacholine (0.25, 5, 100, 2000mM each for 25 min) and 2) endothelium-independent vasodilation induced via administration of 50mM sodium nitroprusside (20-25 min). Responses were evaluated at four skin sites treated with either 1) lactated Ringer solution (Control), 2) 400nM endothelin-1, 3) 3mM HA-1077 (Rho kinase inhibitor), or 4) endothelin-1+HA-1077. Pharmacological agents were intradermally administered via microdialysis. Relative to the Control site, endothelin-1 attenuated endothelium-dependent vasodilation (CVC at 2000mM methacholine, 80±10 vs. 56±15%max, P<0.01); however, this response was not detected when the Rho kinase inhibitor was simultaneously administered (CVC at 2000mM methacholine for Rho kinase inhibitor vs. endothelin-1 + Rho kinase inhibitor sites: 73±9 vs. 72±11%max, P>0.05). Endothelium-independent vasodilation was attenuated by endothelin-1 compared to the Control site (CVC, 92±13 vs. 70±14%max, P<0.01). However, in the presence of Rho kinase inhibition, endothelin-1 did not affect endothelium-independent vasodilation (CVC at Rho kinase inhibitor vs. endothelin-1+Rho kinase inhibitor sites: 81±9 vs. 86±10%max, P>0.05). There was no between-site difference in sweating throughout (P>0.05). We show that in young adults, Rho kinase is an important mediator of the endothelin-1 mediated attenuation of endothelium-dependent and -independent cutaneous vasodilation, and that endothelin-1 does not increase sweating.