Structure-binding studies of the adrenal AT4 receptor:: analysis of position two- and three-modified angiotensin IV analogs

Amino acid substitutions in positions two and three of angiotensin IV (VYIHPF) were carried out to determine which structural features of the side-chains were important for achieving high-affinity binding to bovine adrenal receptors. These studies demonstrated that an activated aromatic ring in the second position side-chain resulted in the highest-affinity binding. Position three required a hydrophobic amino acid to achieve high-affinity binding. Both aliphatic and aromatic side-chains were sufficient to yield high-affinity binding. (C) 1999 Elsevier Science Inc. All rights reserved.