2017 Pharmacology - Pharmacodynamics

Question 1

How do you define drug Efficacy?

Answer 1

it is the strength of a single drug-receptor interaction that evokes a response

Question 2

What are Agonists and what do they cause?

Answer 2

drugs that bind to receptors and produce some effect similar to the response produced by endogenous agents, they possess intrinsic activity

Question 3

What are Antagonists and what do they cause?

Answer 3

drugs that bind to receptors but DO NOT produce an effect, they possess no intrinsic activity.

Question 4

What 2 things affect drug-receptor interactions?

Answer 4

Binding forces Structure Activity Relationships

Question 5

What are the differences between Graded vs. Quantal Dose-Response Curves?

Answer 5

Quantal - based on all or none response, provides estimate of percent of subjects who will respond to any given dose

Graded - based on data from single subjects, provides info about potency and efficacy

Question 6

What does a quantal dose response curve look like?

Answer 6

Question 7

What does a graded dose response curve look like?

Answer 7

X is more potent, lower [x] needed to get EC50

X has a higher efficacy than Y

Question 8

What are 4 key features of Competative Antagonists?

Answer 8

Reversible binding to receptor

Blockade can be overcome by increasing [agonist]

maximal response of agonist is not decreased

agonist dose-response curve in presence of competative antagonist is displaced to the right and parallel

Question 9

What are features of Irreversible Competative Antagonists?

Answer 9

Typically covalently bound

Maximal response is deminished

Cannot overcome antagonist w/ increased agonist concentration

Question 10

What are features of Partial Antagonists?

Answer 10

decrease the maximal response

Question 11

Features of Non-competitive Antagonism?

Answer 11

antagonist does not bind to active site

Question 12

What is an Inverse Agonist?

Answer 12

Binds to receptor site like an Agonist but has the opposite effect of the normal Agonist

Question 13

Understand levels of response for Full agonists, partial agonists, inverse agonists and antagonists.

Answer 13

Question 14

What are two types of changes in receptor sensitivity that can occur?

Answer 14

Desensitization - deminished response, altered binding of drug to receptor, lack or receptors, decreased coupling of drug-receptor complex & signaling

Supersentitization - increased response, can be drug induced or pathophysiological.