Rapid analysis of interaction between six drugs and β2 -adrenergic receptor by injection amount-dependent method.

Drug-protein interaction analysis has become a considerable topic in life science which includes clarifying protein functions, explaining drug action mechanisms and uncovering novel drug candidates. This work was to determine the association constants (KA ) of six drugs to β2 -adrenergic receptor by injection amount-dependent method using stationary phase containing the immobilized receptor. The values of KA were calculated to be (25.85 ± 0.035) × 10(4)  m(-1) for clorprenaline, (42.51 ± 0.054) × 10(4)  m(-1) for clenbuterol, (6.67 ± 0.008) × 10(4)  m(-1) for terbutaline, (33.99 ± 0.025) × 10(4)  m(-1) for tulobuterol, (7.59 ± 0.011) × 10(4)  m(-1) for salbutamol and (78.52 ± 0.087) × 10(4)  m(-1) for bambuterol. This rank order agreed well with the data determined by zonal elution, frontal analysis and nonlinear chromatography, even using different batches of β2 -AR column. A good correlation was found between the association constants by the current method and radio-ligand binding assay. Our data indicates that the injection amount-dependent method is a powerful alternative for rapid analysis of ligand-receptor interactions.