Fig. 6. Computer simulations demonstrate meperidine docking in proximity to the relevant residues for each of the α2adrenoceptors. The residues in the α2A(PHE and THR in orange) and α2C(PHE and TYR in red) adrenoceptors are very dissimilar to their respective, homologous residues in the α2Breceptor (LEU, GLY in green). This suggests possible reasons for subtype-specific high affinity binding of meperidine to the α2Breceptor.