11/12 Pharmadynamics

Question 1

what is pharmacodynamics?

Answer 1

the drugs effects on the body.

Question 2

what are the five different types of biochemical receptors

Answer 2

1. Intracellular. 2. Ligand-regulated enzyms. 3. Cytokine 4. ligand-gated ion channel. 5. G-protien linked

Question 3

describe an intracellular biochemical receptor

Answer 3

a receptor that will bind a lipophilic drug or other drug that enters the cell and binds in the cytoplasm.

Question 4

describe a ligand regulated enzyme

Answer 4

this is a receptor that will bind a ligand on the outside of the cell and then on a transmembrane component: cause a conformational change or other change in the receptor that will turn it into a an active enzyme on the intracellular portion of the receptor.

Question 5

describe a cytokine biochemical receptor:

Answer 5

receptor binds the drug, causing the receptor to bind a ligand on the intracellular portion and then the intercellular portion will act to phosphorilate intracellular molecules

Question 6

Describe ligand-gated ion channel biochemical receptors:

Answer 6

they bind a ligand or other drug that will cause the ion channel to open and allow ions to flow through

Question 7

Describe G-protein coupled biochemical receptors:

Answer 7

they are7 transmembrane receptors, interact with a G-protien and have an effector element and second messenger.

Question 8

what are the possible effector elements of a G-protein?

Answer 8

Enzymes (protien kinase A) or ion channels

Question 9

what are the second messengers of G proteins

Answer 9

cAMP, IP3 and cGMP

Question 10

Non-superimposable mirror images of a drug:

Answer 10

Chiral molecules

Question 11

why would chirality be important for drug delivery?

Answer 11

50% of useful drugs have different chrality with different potentcy or toxicity.

Question 12

Most common drug-receptor interactions use what type of bond?

Answer 12

Electrostatic

Question 13

a drug that binds a physicologic receptor and mimics the regulatory effects of the endogenous signaling compounds

Answer 13

Agonist

Question 14

partial agonist

Answer 14

binds and activates the receptor but does not evoke as great a response as full agonists

Question 15

Allosteric agonist

Answer 15

binds to a site on the receptor remote from the agonist binding site.

Question 16

Inhibiting drug action

Answer 16

mimics agonist drugs by inhibiting the molecules responsible for terminating the action of an endogenous agonist

Question 17

inverse agonist drug action

Answer 17

reduces receptor activity below basal levels observed in the absence of bound ligand (clinical effets similar to competitive antagonist)

Question 18

The level of response vs. log of the drug conc. for a full agonist; partial agonist , inactive compound, and inverse agonist.

Answer 18

Question 19

a drug without regulatory effect that interferes with the ability of the endogenous agonist to activate a receptor

Answer 19

Antagonist

Question 20

Describe Reversible competitive antagonists

Answer 20

reversibly binds to the same site as the agonist. Increases the agonist concentration required for a given degree of response.

Question 21

Irreversibly binds the same site as the agonist. Reduces the maximal effect the agonist can achieve

Answer 21

Allosteric

Question 22

What types of antagonist are non-Competitvie

Answer 22

Irreversible;

Allosteric;

Question 23

Graph of a competitive antagonist

% max effect vs. Log [drug] as you add more and more antagonist

Answer 23

Question 24

Graph of Non-competitive Antagonist in the form of irreversible antagonist:

% max effect vs. [drug] for different amounts of antagonism added

Answer 24

Question 25

Graph of Non-competitive Antagonist in the form of Allosteric antagonist:

% max effect vs. [drug] for different amounts of antagonism added

Answer 25

Question 26

What is the concentration of drug where 50% effect has been achieved?

Answer 26

the EC50 or effective concentration 50

Question 27

What is the difference in potency vs. efficacy?

Answer 27

the potency is the conc. of drug needed to be able to reach % max effect

(greater conc. needed then less potency– look at the right shift in the % effect vs. log[] graph – farther to the right the less potent)

The Efficacy is the ability of the drug to reach a high % effect.

(less % effect reached at high conc. then less efficacy – look at the hight of the final equilibrium of the % effect vs. Log [] graph – smaller height is less efficacy)

Question 28

The graphical representation of the ED-50 dose and the LD-50 dose

Answer 28

Question 29

The dose at which 50% of individuals exhibit the specified effect

Answer 29

Median effective dose (ED-50)

Question 30

I’m prescribing a drug, and I want to know how likely a high dose of the drug is going to kill by patient…given that I work with an average patient that is :-) what do I want to calc?

Answer 30

the Therapeutic Index

TI = TD-50/ED-50 or TI = LD-50/ED-50

where TD=toxic dose; LD = lethal dose; ED=Effective dose

as the number gets smaller, and closer to one, then the drug is more likely to cause problems with any kind of large dose!

Question 31

The dose at which 50% of the individuals exhibit the specified toxic effect

Answer 31

Median toxic dose (TD-50)

Question 32

Median Lethal dose (LD-50)

Answer 32

the does at which 50% of the individuals die

Question 33

hmmm, the patient just had a really infrequent reaction to the drug…what kind of variability is this?

Answer 33

Idiosyncratic variability

Question 34

This person just does not have a very intense effect from this dose of the drug that most people see a large effect from…what do I call this?

Answer 34

Hyporeactive

Question 35

This perosn has a very intense effect from this drug that most have a mild effect…what do I call this variability

Answer 35

Hyperreactive

Question 36

This person takes this drug every day and now it doesn’t seem to effect them at all….?

Answer 36

Tolerance

Question 37

The intensity of response is rapidly diminshed in response to continued drug administraition?

Answer 37

Tachyphylaxis