Wirkungsverst�rkung von Renin und Nierenextrakt an der nierenlosen Ratte

Abstract

1. Experiments were carried out on intact and nephrectomised rats, in order to compare the pressor effects of adrenaline, nor-adrenaline, Pitressin, hog renin, a freshly prepared extract from rats' kidneys, and hypertensin. 2. In the nephrectomised animal, renin and rat-kidney extract produce a rise in blood pressure which, in comparison with the effect observed on intact rats, is characterised by a greater intensity and particularly by a more prolonged duration (several hours). Following nephrectomy, the pressor effect of hypertensin is appreciably intensified, but only slightly prolonged. Pitressin occupies an intermediate position between renin and hypertensin, although its pressor action is less pronounced and of shorter duration than of renin. Nephrectomy produces only a slight intensification in the hypertensive effect of adrenaline and nor-adrenaline. 3. The more marked rise in blood pressure occurring in nephrectomised animals in response to the injection of renin is attributed to a lack of renin or of substances with renin-like properties. It is suggested that the enzymatic release of hypertensin is not the only means by which renin exerts its influence on the blood pressure.