Effect of angiotensinase inhibitors on angiotensin receptors in rabbit aorta
Farruggia, P.; Sachs, S.; Palaic, D.
Molecular Pharmacology 15(3): 525-530
1979
ISSN/ISBN: 0026-895X PMID: 226859 Document Number: 154156
Caproic acid (1 cM) and EDTA (10 mM) blocked the cell membrane angiotensinase of rabbit aorta. Caproic acid significantly increased the maximal response to angiotensin and delayed the relaxation time of contracted aortic strips. EDTA decreased the maximal response and had no effect on relaxation due to EDTA chelating capacity for Ca2+. The binding studies showed an increased angiotensin receptor binding in the presence of angiotensinase inhibitors. The increased maximal response and delayed relaxation time seen with caproic acid may be due to uncovering of additional angiotensin receptors and increased agonist availability at the receptor site after angiotensinase blockade, which stimulates some post-receptor mechanism leading to increased intracellular Ca2+.