Pharmacodynamics

Question 1

Drug actions

Answer 1

Stimulate or inhibit normal cellular functions

Cannot add functions

Question 2

Drug binding to drug targets

Answer 2

Weak: reversible
H bond, ionic, hydrophobic bond

Few are covalent

Question 3

Drug selectivity

Answer 3

Size, shape, and charge of a drug determine whether it binds to a particular receptor

Question 4

Drugs for ion channels

Answer 4

Altering the conductance of ion channels

Eg:
Local anesthetics: diffuse inside to the cytoplasm, bind to specific binding site on channel, close it
Sedative-hypnotics for anxiety
Antiepileptics

Question 5

Drugs for GPCR

Answer 5

60% of prescription

Eg:
Albuterol: bata2-agonist, for asthma
Propranolol: beta-antagonist, for hypertension

Question 6

Drugs for enzyme-linked receptors
Insulin receptor
EGFR

Answer 6

Anticancer drug

Gain-of function mutations in these tyrosine kinase R can lead to cancer
Important in cell growth and differentiation

Eg:
Imatinib: for leukemia

Question 7

Members of nuclear R superfamily

Answer 7

Steroid hormones
Thyroid hormones
Vitamin D

Question 8

Drugs targeting enzymes

Answer 8

Inhibit enzyme activity

Eg:
Aspirin
Ibuprofen
Omeprazole

Question 9

Drugs targeting transporters

Answer 9

Target nt transporter for psychiatric disorders

Eg:
Antidepressant drugs: blocking serotonin reuptake

Question 10

Drugs targeting structural proteins

Answer 10

Bind to tubulin, prevent polymerization, arrest cells in metaphase

Question 11

Drugs not binding to receptors

Answer 11

Antacids: neutralize gastric acid

Question 12

2 types of dose-response relationships

Answer 12

Graded

Quantal

Question 13

Graded dose-response curves

Answer 13

E=Emax*C/(C+EC50)

Hyperbolic

Question 14

Receptor binding of drugs

Answer 14

B=Bmax*C/(C+KD)

KD:concentration of drug required to occupy half of the receptors
Affinity: measure the strength of drug-receptor complex

Question 15

Graded dose-response curves

Drug effect agains log of C

Answer 15

Sigmoid curve

Question 16

Compare the value of eE50 and KD

Answer 16

KD is larger than EC50

Because an agonist does not have to occupy all receptors to evoke a full response

Question 17

Spare receptors

Answer 17

Indicating that there is signal amplification

Question 18

EC50 in whole animal experiments

Answer 18

Is ED50 = log of drug dose since cannot measure drug concentration

Question 19

Efficacy

Answer 19

Magnitude of the response a drug produces

=Emax

Question 20

Potency

Answer 20

C of the amount of drug necessary to produce an effect of a given magnitude

Measured by EC50

Question 21

Agonist

Answer 21

Bind and activate R

Has affinity and efficacy

Question 22

Antagonist

Answer 22

Inhibit agonist

Has affinity but no efficacy
Bind and do nothing

Question 23

Receptor antagonism

Answer 23

Competitive

Noncompetitive

Question 24

Nonreceptor antagonism

Answer 24

Physiological

Chemical

Question 25

Reversible competitive antagonist

Answer 25

EC50 increase

Same Emax

Question 26

Irreversible competitive antagonism

Answer 26

Reduced Emax

Same plot as allosteric

Question 27

Noncompetitive antagonism

Answer 27

Allosteric

Reduced Emax

Question 28

Physiological antagonism

Answer 28

1 drug opposes another drug, thru different receptors

Eg:
Epinephrine vs histamine

Question 29

Chemical antagonism

Answer 29

Reacts chemically with an agonist to form an inactive product

Eg:
Protamine + charged
Counteracts heparin, anticoagulant - charged

Question 30

Partial agonist

Answer 30

Produce lower Emax than full agonist

Competitive antagonist to full agonist

Question 31

Inverse agonist

Answer 31

Reverse the constitutive activity of R

Question 32

Therapeutic index

Answer 32

TI=TD50/ED50
Or LD50/ED50

Safe drug: large LD small ED

Question 33

Therapeutic window

Answer 33

Min effective C and min toxic C