When a drug causes a change in the cell membrane, preventing additional stimulation of the cell no matter how much stimulation is offered, that drug is called a:
A) competitive agonist.
B) competitive antagonist.
C) noncompetitive antagonist.
D) noncompetitive agonist.

Question

Quizplus · Accepted Answer

A noncompetitive antagonist causes a change in the cell membrane that prevents any further stimulation of the cell, regardless of how much stimulation is offered. This is different from a competitive antagonist, which competes with the natural ligand for binding to the receptor but can still be overcome by increasing the concentration of the natural ligand. Noncompetitive agonists also cause changes in the cell membrane but result in increased stimulation rather than decreased stimulation. Competitive agonists compete with the natural ligand for binding to the receptor and can produce the same effects as the natural ligand when bound.

When a Drug Causes a Change in the Cell Membrane