Module 7

Question 1

Study of what the drug does to the body.

Answer 1

Pharmacodynamics

Question 2

Study of the biochemical and physiological effects of drugs and the mechanisms by which drugs produce effects.

Answer 2

Pharmacodynamics

Question 3

To evaluate the pharmacodynamics of drugs, we look at __________.

Answer 3

dose-response curves

Question 4

Dose-response curves are _______, which means that the response increases as the dose increases.

Answer 4

monotonic

Question 5

Importantly, dose response curves are not linear, thus we usually look at them as _____________ plots.

Answer 5

semi-logarithmic

Question 6

What are the phases of the semi-log dose response curve.

Answer 6

Phase 1 - Doses are too low to elicit a clinically relevant response
Phase 2 - the response is graded and nearly linear
Phase 3 - Larger doses do NOT lead to greater responses - larger doses may lead to toxicity.

Question 7

Measure of how effective a drug is at a given dose

Answer 7

Efficacy

Question 8

Maximum effect that a drug is capable of achieving

Answer 8

maximal efficacy

Question 9

Maximal efficacy is read off the dose response curve by looking at what?

Answer 9

Maximum height

Question 10

Healthcare professionals often titrate the dose of a drug. What does this mean?

Answer 10

This means they start with a low dose of the drug and slowly increase the dose while monitoring the patient’s response

Question 11

Refers to the amount of drug required to elicit a pharmacological response.

Answer 11

potency

Question 12

In order to compare potency, what is necessary?

Answer 12

Both drugs MUST produce the same therapeutic effect

Question 13

A more potent drug will require a ______ dose to achieve the desire effect than a less potent drug.

Answer 13

smaller

Question 14

Potency is determined by comparing the dose required to produce the half-maximal response - the ____.

Answer 14

ED50

Question 15

Most drugs act on ________ _________.

Answer 15

cellular macromolecules

Question 16

Give an example of a drug that does not act on cellular targets.

Answer 16

Antacids

Question 17

Protein that a drug binds to and produces a measurable response.

Answer 17

receptor

Question 18

What are the 4 most important types of receptors?

Answer 18

1 - Ligand-gated ion channels
2 - GPCR
3 - Enzyme-linked receptors
4 - Intracellular receptors

Question 19

What is an important example of a ligand-gated ion channel?

Answer 19

GABA receptor

Question 20

Describe the action of the GABA receptor.

Answer 20

When GABA (NT) binds to the GABA receptor, it causes the opening of a channel that allows the ion chloride to flow into the cell

Question 21

Drugs that are part of the _______ class are able to bind to the GABA receptor and allow chloride to enter the cell.

Answer 21

benzodiazepine

Question 22

Activation of the GABA receptor causes _______ and muscle _______ mediated by the increased intracellular chloride.

Answer 22

sedation

relaxation

Question 23

Describe the time frame of response for ligand-gated ion channels.

Answer 23

Responses to these receptors are very rapid, having a duration of milliseconds

Question 24

Approximately __% of marketed drugs mediate their effects through actions on GPCRs.

Answer 24

50

Question 25

What are the three components of GPCRs?

Answer 25

Seven transmembrane spanning protein receptor
G-protein with three subunits
Effector molecule

Question 26

Describe the timeframe of activation of GPCRs.

Answer 26

Result in a response that lasts from seconds to minutes in duration.

Question 27

What endogenous NTs mediate their effects by binding to GPCRs?

Answer 27

NE, serotonin, histamine

Question 28

Describe enzyme-linked receptors.

Answer 28

Receptor side is on the outside of the cell membrane

Catalytic side in on the inside

Question 29

Describe the time frame of the response for enzyme-linked receptors.

Answer 29

Very rapid - seconds

Question 30

What is an example of an enzyme-linked receptor in the body?

Answer 30

Insulin binding to the insulin receptor - causes enzyme-mediated phosphorylation and activation of an intracellular effector (causes increased translocation of glucose transporters to the cell membrane)

Question 31

What is the net effect of insulin binding to its receptor?

Answer 31

Increased cellular glucose uptake and utilization

Question 32

Intracellular receptors reside completely inside the cell and are also called __________ _________.

Answer 32

transcription receptors

Question 33

In order for ligands to access intracellular receptors, what must they be able to do?

Answer 33

Cross the cell membrane by diffusion or via drug transport proteins

Question 34

Binding of the ligand to the intracellular complex causes translocation of this complex to the _______ and binding to ______.

Answer 34

nucleus

DNA

Question 35

When the ligand-receptor complex binds to DNA, what occurs?

Answer 35

RNA transcription is stimulated, with protein synthesis occurring hours to days later

Question 36

Ligands to intracellular receptors are typically highly ______ _______. What are some endogenous examples?

Answer 36

lipid soluble

Steroid molecules such as testosterone and estrogen

Question 37

Drugs that are ________ will bind to only one receptor and therefore will be less likely to produce ______ _______.

Answer 37

selective

side effects

Question 38

IF a drug binds to only one receptor, can there be side effects?

Answer 38

Yes, the receptor may be located in many different organs.

Question 39

What is the classical view of drug selectivity?

Answer 39

Lock and key hypothesis