S-(+)-1-[(4-(Dimethylamino)-3-methylphenyl)methyl]-5-(diphenylacetyl)-4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridine-6-carboxylic acid hydrate di(trifluoroacetate) salt

PD 123319 is shown to discriminate between two subclasses of AII receptors in many different tissues. ¹²⁵ I-AII specifically label two classes of binding sites for AII in a membrane preparation of bovine adrenal glomerulosa cells. The first class (DuP-753 sensitive) represents approximately 85% of the total binding sites for AII and possesses a high affinity (IC ₅₀ of 92.9 nM) for DuP-753. PD-123319 does not have any effect on ¹²⁵ I-AII binding to this site. The second class of binding sites is more sensitive to PD-123319, with an IC ₅₀ of 6.9 nM , and has a much lower affinity for DuP-753 (IC ₅₀ around 10 microM).

IC50: 34 nM (AT2 Receptor)