Drug-Receptor Interaction

Question 1

Define pharmacodynamics

Answer 1

The effect of a drug on the body

Question 2

Define pharmacokinetics

Answer 2

The effect of the body on the drug

Question 3

What is the role of pharmacodynamics in therapeutics?

Answer 3

Pharmacodynamics causes the positive and negative (toxic) effects of a drug because of interactions with specific cellular target molecules (receptors)

Question 4

What are the 8 receptor classes?

Answer 4

Enzymes, ionotropic receptors or ion channels, metabotropic receptors, kinase linked and related receptors, nuclear receptors, cytoskeleton or structural proteins, transporters or carrier proteins; nucleic acids, membranes, fluid compartments (non-protein receptors)

Question 5

How can variation in receptor families allow for multiple types of compounds to have pharmacological consequences?

Answer 5

Many of the receptor subfamilies can be coupled to an executioner or effector that can cause diverse cellular effects

Question 6

Define Agonist

Answer 6

A drug that activates a receptor

Question 7

What is a full agonist?

Answer 7

A drug that mimics the physiologic agonist

Question 8

What is a partial agonist

Answer 8

A drug that activates receptors but is unable to elicit the maximum response of the receptor system

Question 9

What is an inverse agonist?

Answer 9

An agonist that binds to the same receptor as an agonist but causes the opposite effect

Question 10

What is an antagonist?

Answer 10

A drug that is unable to trigger receptor activation but physically interacts with the receptor

Question 11

What is a competitive antagonist?

Answer 11

A antagonist that occupies the receptor and prevents binding of physiological or drug ligands

Question 12

What is a non-competitive or irreversible antagonist

Answer 12

A drug or physiological compound that covalently binds at the active site of an enzyme and irreversibly inhibits it

Question 13

What is an allosteric inhibitor

Answer 13

A antagonist that binds at sites other than the active site to cause a conformational change that prevents an enzyme from binding to a physiological substrate

Question 14

What is the EC50?

Answer 14

The concentration of a drug required to produce 50% of the maximal effect

Question 15

What is plotted in a drug response curve?

Answer 15

Drug effect (y axis) against logarithm of the dose or concentration (x-axis)

Question 16

Is a drug more or less potent if it is shifted to the left with the same EC50 on a drug response curve?

Answer 16

More

Question 17

Does the drug have a greater or lesser maximum efficacy if the curve has a greater response?

Answer 17

Greater

Question 18

What is the difference between drug potency and efficacy

Answer 18

Efficacy is the effectiveness of a drug and potency is the concentration of a drug that is required to produce 50% of the maximum effect

Question 19

What does therapeutic index refer to?

Answer 19

The ratio of the toxic dose to effective dose in 50% of individuals. A narrow therapeutic index is with highly potent drugs

Question 20

Define therapeutic drug monitoring

Answer 20

A narrow therapeutic range may have its dosage adjusted according to the blood levels of the person taking it. For example TDM is used with lithium for bipolar disorder