Exam 4: Drug Receptors

Some drugs affect the function of the adenylate cyclase,an enzyme located on the inner surface of the cell membrane.This enzyme is responsible for hydrolyzing adenosine triphosphate (ATP)into _____,which acts as a second messenger that activates other enzymes (i.e.,protein kinases)throughout the cell.

In contrast to an agonist,a pharmacologic antagonist

A noncompetitive antagonist

The primary location for receptors that recognize drugs and endogenous compounds is

A drug that binds readily to available receptors even if the concentration of drug is relatively low is said to have _______ for that receptor.

Overstimulation of postsynaptic receptors may lead to a decrease in responsiveness of the receptors.A fairly brief and transient decrease in receptor responsiveness is known as _____,whereas a more prolonged process in which the actual number of available receptors is diminished is known as _________.

Signals from the surface receptor are transduced into the appropriate response within the cell via intermediate regulatory proteins that are activated by binding guanine nucleotides,hence they are often termed ______ proteins.

A drug that binds to a receptor and directly initiates a change in the function of the cell is referred to as

The ability of a drug to bind to its receptor can be influenced by local chemicals such as guanine nucleotides,ammonium ions,and divalent cations.These local regulators are commonly known as _____.

A drug that fails to evoke a maximal response even though it occupies all available receptors is known as

The acetylcholine receptor located on the postsynaptic membrane of the skeletal neuromuscular junction is an example of a membrane receptor that