AFTER THE CHARACTERIZATION and synthesis of angiotensin amide and the discovery of a depressor fraction in blood, Jablons1,2 suggested the possible use of intradermally injected angiotensin amide as a diagnostic tool in hypertension. He theorized that individuals might have varied responses to angiotensin amide depending on the relative balance of pressor material (angiotensin II) and depressor material (angiotensin inhibitor) present in the circulatory system. Jablons found that the characteristic circumscribed area of blanching and induration produced by the intradermal injection of 0.05 to 0.1μg of angiotensin amide in saline solution persisted longer in hypertensive patients than in normal persons. Preliminary studies had indicated that more than 90% of the normal persons tested had areas of induration and blanching that persisted for less than 30 min, whereas more than 90% of the hypertensive persons had induration and blanching that lasted for more than 30 min.
The present study was