During the reanimation procedure in the ER doctors gave a patient an injection of epinephrine to increase his heart rate and blood pressure. The heart rate and blood pressure went up but not enough. The second dose of the same drug seemed not to have an effect. What is a possible explanation for this result?
A) the receptors reached the saturation level with the drug between the first and second dose
B) the activation energy of the receptors went down between the first and second dose
C) the receptors changed their transduction pathway between the first and second dose
D) the cell expressed more receptors between the first and second dose

Question

Quizplus · Accepted Answer

Option A is the most likely explanation as the receptors may have reached saturation where they cannot bind any additional drug molecules, leading to a decreased response to the second dose. Option B and C are unlikely as they suggest changes in the receptors themselves, which is not typical for a single administration of a drug. Option D is also unlikely as it would lead to an increased response to the second dose, not a decreased response.

During the Reanimation Procedure in the ER Doctors Gave a Patient