New aspects of aldosterone regulation

Evidence is presented that points to an important role of the COOH-terminal heptapeptide fragment of angiotensin II, (Des-Asp) angiotensin II, in the regulation of aldosterone biosynthesis. In favor of this view are the demonstrations that (1) the heptapeptide is as effective as angiotensin II in stimulating aldosterone secretion, (2) heptapeptide antagonists are potent and specific inhibitors of angiotensin II-induced steroidogenesis, and (3) the heptapeptide can be generated readily in plasma and locally in tissues. The concept of specific adrenal cortical receptors for the heptapeptide also allows a possible explanation for the observation that arterial pressure-angiotensin II-aldosterone inter-relations often are inconsistent.