Verstärkung der pressorischen Wirkung von Renin, drucksteigernden Peptiden und adrenergischen Wirkstoffen nach Nephrektomie und bei Überdosierung von Cortexon und Kochsalz an der Ratte

Summary

• 1. In the nephrectomised rat and in the rat overdosed with cortexone and salt comparative investigations have been performed on the intensity of the hypertensive reaction following the intravenous injection of adrenaline and nor-adrenaline, renin, natural and synthetic hypertensin, vasopressin, and ocytocin.

• 2. In the nephrectomised animal there is an increase of pressor response dependent on the dose for renin and the various peptides while no enhanced activity for the adrenergic substances has been found.

• 3. In the animals pretreated with cortexone and salt, pressor response to the adrenergic substances as well as to renin and the hypertensive peptides is increased, the maximal height of and relative increase in blood pressure being generally higher than in the nephrectomised rats.

• 4. Two mechanisms seem to be responsible for the increase in hypertensive activity of the substances examined:

• a) a decrease in the inactivating capacity for renin and peptides, resulting either from extirpation of the kidney or from diminution of the content of pressor active material (renin?) in the kidney.

• b) an increased sensitivity of the arterial system to hypertensive stimuli, probably due to a higher sodium, potassium and water content of the arterial and arteriolar wall.

• 5. The possible significance of these mechanisms for the pathogenesis of hypertension is discussed.