Which changes most likely occurred in cardiac beta receptors after 1-2 weeks of therapy?

Beta-receptor number increased in time

Learning objective: explain the most likely consequence of chronic blockade of drug receptors Answer: C When receptors are blocked chronically the number of those receptors may increase in time, a process called up-regulation of receptors or sensitization or supersensitivity, since the effector response will be greater than usual, if the blockade is abruptly removed. A) By definition spare receptors are not involved in receptor activation or blockade. B, E) Since the number of receptors increases in time, G-protein and second messengers , if something, would increase, not decrease. D) Receptor intrinsic activity refers to the amount of activation each receptor is able to produce when bound by an agonist drug. If something, this amount would increase, not decrease.