Endothelial role in the cyclic transmural pressure–induced vasodilation. The cyclic transmural pressure induced the vasodilation in precontracted coronary and skeletal muscular small arterial segments, and the vasodilation was inhibited by nonselective NOS inhibitor or denuded endothelium. (A) Cyclic transmural pressure–induced vasodilation persisted for at least 20 min. (B) Administration of L-NAME caused a dynamic vasoconstriction during cyclic transmural pressure. SNP, sodium nitroprusside (a NO donor). (C) Cyclic transmural pressure–induced vasodilation was inhibited by the mechanical removal of endothelium by a vessel diameter–matched wire.