Endothelium-dependent vasodilatation in the perfused mesenteric vascular bed of the rat

A new technique for studying the newly discovered endothelium derived relaxant factor in producing relaxations of vascular smooth muscle cells by using an isolated preparation of perfused mesenteric arterial bed is discussed. The preparation was precontracted with suitable spasmogens and the effect of various vasodilators on this preparation with and without the presence of an intact endothelium was studied. Different receptor specific drugs were used for investigating the nature of this substance. The study confirms the essential role of this substance in the production of relaxations of vascular smooth muscle cells and outlines the suitability of this technique for researching into the nature of this substance