Divergent signaling mechanisms for venous versus arterial contraction as revealed by endothelin-1

These studies outline a new and fundamental difference between venous and arterial smooth muscle, in terms of excitation-contraction coupling and calcium mobilization during endothelin-1-induced contraction, and further reinforce the heterogeneity of vascular smooth muscle. Because changes in venous capacitance are associated with a multitude of medical conditions, including syncope, hemorrhage, shock, heat stroke, and congestive heart failure, these findings also present new potential therapeutic targets (specifically diacylglycerol interference) specific to veins.