Pharmacodynamic Principles - 1

Question 1

the study of what the drug does to the body

Answer 1

pharmacodynamics.

Question 2

what does pharmacodynamics include? “HINT:3”

Answer 2

1- the action of the drug on the body (beneficial and harmful).
2- influence of drug concentrations on the magnitude of response.
3- modification of the action of one drug by another drug.

Question 3

how do antacids work?

Answer 3

neutralization of gastric HCL

Question 4

how do chelating agents work?

Answer 4

chelation of heavy metals.

Question 5

give examples of chelating agents?

Answer 5

EDTA and dimercaprol.

Question 6

when are chelating agents used?

Answer 6

in cases of heavy metal poisoning.

Question 7

give an example diuretic?

Answer 7

mannitol.

Question 8

give an example of a laxative?

Answer 8

mag. sulphate.

Question 9

how do diuretics and laxatives work?

Answer 9

osmotic activity.

Question 10

how does activated charcoal work?

Answer 10

adsorptive property.

Question 11

give an example of a radioisotope?

Answer 11

l-131

Question 12

how do radioisotopes work?

Answer 12

radioactivity.

Question 13

majority of drugs act by binding to their _____ or _____________

Answer 13

targets or specific receptors.

Question 14

a macromolecule or binding site located on the surface or inside the cell that serves to recognize the signal molecule/drug and initiate response to it, but itself has no other function.

Answer 14

receptor.

Question 15

list the 4 receptor families?

Answer 15

1- ligand - gated ion channels.
2- G-protein coupled receptors.
3- enzyme linked receptors.
4- cytosolic (nuclear) receptors.

Question 16

where are receptors found in ligand-gated ion channels?

Answer 16

coupled directly to membrane ion channels

Question 17

speed of response in ligand-gated ion channels is?

Answer 17

millisecond.

Question 18

give an example of a drug that acts on ligand-gated ion channels?

Answer 18

neurotransmitters.

Question 19

where are receptors in G-protein coupled receptors found?

Answer 19

bound to cell membrane and coupled intracellular effector system by a g-protein.

Question 20

speed of response in g-protein coupled receptors?

Answer 20

seconds.

Question 21

give an example of a drug that acts on GPCR?

Answer 21

catecholamines.

Question 22

binding of a drug to an enzyme linked receptor results in?

Answer 22

increased enzymatic activity.

Question 23

speed of response in an enzyme linked receptor is?

Answer 23

minutes to hours.

Question 24

give an example of a drug that acts on enzyme linked receptors?

Answer 24

receptors for growth hormone and insulin

Question 25

what is the function of a cytosolic (nuclear) receptors?

Answer 25

regulate DNA transcription and protein synthesis.

Question 26

speed of response in a cytosolic (nuclear) receptors?

Answer 26

hours to days.

Question 27

give an example of a drugs that act on cytosolic (nuclear) receptors?

Answer 27

steroid receptors, thyroid receptors.

Question 28

list the 4 different G proteins based on alpha subunit?

Answer 28

1- Gs 2- Gi 3- Go 4- Gq

Question 29

what is the function of Gs?

Answer 29

adenylyl cyclase activation, Ca2+ channel opening.

Question 30

what is the function of Gi?

Answer 30

adenylyl cyclase inhibition, K+ channel opening.

Question 31

what is the function of Go?

Answer 31

Ca2+ channel inhibition.

Question 32

what is the function of Gq?

Answer 32

phospholipase C activation.

Question 33

list 5 examples of GPCRs?

Answer 33

1- muscarinic receptor (M2): Gi,Go. 2- muscarinic (M1): Gq. 3- B adrenergic: Gs. 4- Alpha 1 adrenergic: Gq. 5- alpha 2 adrenergic: Gi.

Question 34

list the 4 mechanisms of drug action?

Answer 34

1- enzyme inhibition. 2- transporters. 3- alter microbial processes. 4- incorporation into larger molecules.

Question 35

list 2 examples of drugs that inhibit enzymes?

Answer 35

1- aspirin inhibits cyclooxygenase enzyme. 2- allopurinol inhibits xanthine.

Question 36

give an example of drug that uses transporters?

Answer 36

blockade of anion transport in renal tubule by probenecid increases uric acid excretion.

Question 37

give an example of a drug that alters microbial processes?

Answer 37

penicillin interferes with formation of bacterial cell wall.

Question 38

give an example of a drug that incorporates into larger molecules?

Answer 38

5-flurouracil, an anticancer drug, is incorporated in place of uracil.

Question 39

list the 3 types of therapeutic biologics?

Answer 39

1- genetically engineered enzymes and monoclonal antibodies. 2- genetically modified viruses and microbes. 3- gene therapy products.

Question 40

give an example of generically modified viruses and microbes?

Answer 40

genetically modified live oncolytic herpes virus to treat melanoma.

Question 41

give an example of gene therapy products?

Answer 41

using viruses as vectors to replace genetic mutations.

Question 42

Number of drug receptor complexes determines ______?

Answer 42

Amount of response

Question 43

Receptors are responsible for _______?

Answer 43

Selectivity of drug action

Question 44

Any molecule which attaches selectively to particular receptors or sites?

Answer 44

Ligand

Question 45

List the 4 types of ligands?

Answer 45

1- agonist. 2- antagonist. 3- partial agonist. 4- inverse agonist.

Question 46

Agent which activates the receptor to produce an effect similar to the psychological signal molecule?

Answer 46

Agonist

Question 47

Which ligand has both affinity and a maximal intrinsic activity (IA=1)?

Answer 47

Agonist

Question 48

Give an example of a drug and which receptor is it an agonist to?

Answer 48

Salbutamol (B2 agonist).

Question 49

Which drug produces longer bronchodilation than adrenaline?

Answer 49

Salbutamol

Question 50

An agent which prevents the action of an agonist on a receptor but does not have any effect of its own?

Answer 50

Antagonist

Question 51

Which ligand has affinity and zero intrinsic activity (IA=0)?

Answer 51

Antagonist

Question 52

Give an example of a drug and which receptor are they an antagonist to?

Answer 52

Propanol is a B antagonist (B blocker)

Question 53

An agent which activates the receptor to produce submaximal effect but antagonizes the action of a full antagonist?

Answer 53

Partial agonist

Question 54

Which ligand has affinity and submaximal intrinsic activity (IA between 0 and 1)?

Answer 54

Partial agonist

Question 55

Give an example of a partial and which receptor?

Answer 55

Pindol is a partial agonist at B receptor.

Question 56

An agent which activates a receptor to produce an effect in the opposite direction to that of the agonist?

Answer 56

Inverse agonist

Question 57

Which ligand has affinity and intrinsic activity (IA = between 0-1)

Answer 57

Inverse agonist

Question 58

Give an example of an agonist, their inverse agonist , which receptor do they work on, and their effects?

Answer 58

Benzodiazepines, produce sedation, anxiolysis and control convulsions (GABA receptor agonist). B-Carbolines (inverse agonist of GABA receptor), produce stimulation, anxiety and convulsions.

Question 59

Increase in number of receptors

Answer 59

Up regulation of receptors

Question 60

Decrease in number of receptors

Answer 60

Down regulation of receptors

Question 61

Up regulation happens by continued presence of an ______ or absence of _______

Answer 61

Presence of Antagonist. Absence of Agonist.

Question 62

MI can be precipitated on abrupt withdrawal of which drugs?

Answer 62

Beta-blockers

Question 63

How can abrupt cessation of B-blockers cause MI?

Answer 63

Continuous use of beta-blockers, up regulation of beta receptors, on abrupt cessation, endogenous epinephrine acts on large number of beta receptors, MI

Question 64

Down regulation of receptors happiness because of a continued presence of an _____

Answer 64

Presence of an agonist

Question 65

List the 2 factors that can bring about down regulation of receptors?

Answer 65

1- internalization of the receptor. 2- decreased synthesis/ increased destruction of the receptor.

Question 66

Asthma patients treated continuously with ______ become ______ responsive to them

Answer 66

Beta agonist. Less.

Question 67

Dose response curve is which shape?

Answer 67

Rectangular hyperbola

Question 68

When response is plotted again log(dose), the curve becomes which shape?

Answer 68

Sigmoid.

Question 69

Linear response is seen in the ______% response zone

Answer 69

30-70%

Question 70

Amount of drug needed to produce the same response

Answer 70

Potency

Question 71

Potency is important for what?

Answer 71

Choosing the dose of the drug

Question 72

10 mg of morphine = 100 mg of pethidine as an analgesic. Which drug is more potent?

Answer 72

Morphine

Question 73

The maximal response that can be elicited by the drug

Answer 73

Efficacy

Question 74

Efficacy is important for what?

Answer 74

Choosing the drug

Question 75

10 mg of morphine can relive chest pain of MI. Very high dose of aspirin is not able to relieve the same chest pain. Which drug has higher efficacy?

Answer 75

Morphine

Question 76

Small increase is dose will markedly increase the response

Answer 76

Steep slope.

Question 77

Little increase in response occurs over a wide dose range?

Answer 77

Flat slope

Question 78

Gap between therapeutic effect DRC and the adverse effect of DRC

Answer 78

therapeutic index

Question 79

Therapeutic index is expressed by what?

Answer 79

TI = LD50/ED50 LD50 = dose which kills 50% of recipients. ED 50= dose which produces specified effect in 50% recipients.

Question 80

List the 2 factors that bound the therapeutic window/ range?

Answer 80

1- dose which produces minimal therapeutic effect. 2- dose which produces maximal acceptable adverse effect

Question 81

Drugs with wide therapeutic range are _____ at high doses?

Answer 81

Safe

Question 82

Give an example of a drug with wide therapeutic range which are safe at high doses

Answer 82

Paracetamol

Question 83

Drugs with a narrow therapeutic range can be _____ at slight increase in dose

Answer 83

Toxic

Question 84

Give an example of a drug with a narrow therapeutic range which can be toxic at slight increase in dose?

Answer 84

Theophylline.