For many years structural studies of the angiotensin II type 1 receptor (AT1R) solely relied on mutagenesis experiments combined with homology modeling. The recent publication of the co-crystallized structures of AT1R with the antagonists ZD7155 and olmesartan allows comparative studies. In this chapter the binding modes of olmesartan in the crystal structures and the homology models are compared utilizing mutagenesis data. The obtained results suggest that both homology and crystal structures should be used for future rational drug design. Of paramount importance are these co-crystallized structures or homology models to be simulated in a lipid bilayer environment that mimics the biological.
Keywords: Angiotensin II type 1 receptor; Homology modeling; Induced fit docking; Molecular dynamics; Quantum-polarized ligand docking.