Consider first equilibrium binding for the simple reversible reacion scheme between a free receptor R and a free ligand L to form a receptor/ligand complex C, as illustrated above.
Fig 2-14
Schematic representation of several possible relationships between multiple receptor states. Ligand binding and dissociation from receptors are shown by arrows and associated rate constants kfi and kri, respectively (all models). Interconversions of receptor and complex states are shown with rate constants k12, k21, k'12, and k'21 (models C and D only).