PT  - JOURNAL ARTICLE
AU  - T B Chen
AU  - V J Lotti
AU  - R S Chang
TI  - Characterization of the binding of [3H]L-158,809: a new potent and selective nonpeptide angiotensin II receptor (AT1) antagonist radioligand.
DP  - 1992 Dec 01
TA  - Molecular Pharmacology
PG  - 1077--1082
VI  - 42
IP  - 6
4099  - http://molpharm.aspetjournals.org/content/42/6/1077.short
4100  - http://molpharm.aspetjournals.org/content/42/6/1077.full
SO  - Mol Pharmacol1992 Dec 01; 42
AB  - [3H]L-158,809, a new potent and AT1-selective nonpeptide angiotensin II receptor antagonist, bound saturably and reversibly to rat adrenal membranes. Scatchard and Hill plot analyses indicated a single class of high affinity (Kd = 0.66 nM) binding sites. The relative potencies of various angiotensin II-related peptide and nonpeptide antagonists in displacing [3H]L-158,809 binding correlated with their potencies in displacing the binding of 125I-Sar1,Ile8-angiotensin II to adrenal AT1 receptors. [3H]L-158,809 binding to adrenal membranes was not affected by addition of guanosine-5'-(beta,gamma-imido)triphosphate or various pharmacological agents known to interact with other common peptide and nonpeptide receptor systems. The potencies of angiotensin II receptor agonists, but not antagonists, in inhibiting specific [3H]L-158,809 binding were decreased in the presence of guanosine-5'-(beta,gamma-imido)triphosphate. Specific [3H]L-158,809 binding was also observed in rat liver and kidney. Collectively, the data indicate that [3H]L-158,809 represents a new, potent, nonpeptide, antagonist radioligand suitable for the study of angiotensin II AT1 receptors.