Figure 5.

Effects of varying receptor/coupling protein stoichiometry on relative agonist activity. The receptor mediates cellular response through activation of two effectors 1 and 2. Agonist A produces a relatively uniform activation of both response effectors, whereas agonist B is biased towards effector-2. In cells with an increased stoichiometric ratio of receptor to effector 2, the response to agonist B will be disporportionateloy augmented to yield a different relative potency ratio for the two agonists in the two systems.