The Comparative Effects of Angiotensin and Noradrenaline on Consecutive Vascular Sections

Abstract

The action of 1‐noradrenaline and angiotensin on the resistance and the capacitance vessels in a skin‐muscle region of the cat was studied by means of a technique recently described by Mellander (1960). Intravenous and close arterial infusions of the two substances showed that the constrictor effect of angiotensin on the resistance vessels is greater than that of corresponding amounts of noradrenaline. In the capacitance section, on the other hand, the constrictor responses to noradrenaline by far exceed those to angiotensin. On the basis of these results it is suggested that noradrenaline ‘receptors’ are to be found on the arterial as well as the venous side of the circulation, while angiotensin ‘receptors’ are essentially confined to the smooth muscles of the precapillary vascular region.