An experiment is carried out to evaluate the effects of drug A on the hemodynamic effects of epinephrine. Two groups of fit volunteers are chosen. The first group only receives low-dose epinephrine, and its effects on diastolic blood pressure and heart rate are measured and shown below (epinephrine group). The second group is given drug A before being given low-dose epinephrine, resulting in a new set of curves (epinephrine + drug A group). Which of the following medications is most likely to be drug A?

Question

An experiment is carried out to evaluate the effects of drug A on the hemodynamic effects of epinephrine. Two groups of fit volunteers are chosen. The first group only receives low-dose epinephrine, and its effects on diastolic blood pressure and heart rate are measured and shown below (epinephrine group). The second group is given drug A before being given low-dose epinephrine, resulting in a new set of curves (epinephrine + drug A group).  Which of the following medications is most likely to be drug A?

Quizplus · Accepted Answer

Eductional Objective: Epinephrine increases systolic blood pressure (alpha1 + beta 1) and heart rate (beta1), and depending on the dose, either increases or decreases diastolic blood pressure (either  alpha1 or beta 2 predominates). Propranolol pretreatment eliminates the effects of epinephrine (vasodilation and tachycardia), leaving only the effect (vasoconstriction).

An Experiment Is Carried Out to Evaluate the Effects of Drug