Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MDTI > Pharmacodynamics > Flashcards

Pharmacodynamics Flashcards

1
Q

pharmacodynamics

A

what the drug does to the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

two concepts of pharmacodynamics

A

receptor activation & dose response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

four ways a drug can bring about an effect

A
  1. drug/receptor complex=effect
  2. drug/receptor complex=effector molecule=effect
  3. drug/receptor complex=activation of coupling molecule=effector molecule=effect
  4. drug/receptor complex=inhibition of endogenous activator metabolism=increased activator=increase effect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

receptor

A

a protein that binds a signaling molecule and in doing so generates a signal of its own

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

constitutively active receptor

A

receptors that remain in active conformation even in absence of agonist binding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

agonist

A

a molecule that binds to and activates a receptor to bring about an effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

full agonist

A

drug/agonist that saturates receptor pool, binds to active form, and stabilizes it so that large percent is in Ra-D form. brings about higher maximum response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

partial agonist

A

drug with low intrinsic activity. binds to Ra and stabilizes it so that a low % stays in Ra-D pool regardless of dose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

inverse agonist

A

drug has higher affinity for inactivated receptor and stabilizes large fraction of Ri-D pool. constitutive activity of receptor is lost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

antagonist

A

molecule that prevents activation of receptor by an agonist by binding to the active site. maintain same level as constitutive activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

potency

A

concentration of drug required to achieve a certain effect (EC50: half of the maximum effect)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

efficacy

A

magnitude of the drugs action at the limit of its concentration (Emax, plateau)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

action of allosteric activator

A

amplifies agonist by binding to separate site on receptor. increases efficacy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

allosteric inhibitor

A

binds to separate site of receptor and cause conformational change that prevents agonist from binding or lowers its affinity once bound. changes the maximal response of the drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

competitive inhibition

A

fights for binding site with agonist. causes reduction in response but ultimately drug still reaches maximal effect. can be overcome by increasing concentration of agonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

dose response relationship

A

receptors largely determine the quantitative relationship between dose or concentration of drug and pharmacologic effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

5 types of transmembrane signaling mechanisms

A

steroid receptors, cytokine receptors, receptor tyrosine kinase, ion channel, GCPRs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

steroid receptors

A

a lipid soluble chemical signal crosses the plasma membrane and acts on an intracellular receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

cytokine receptors

A

signal binds to the EC domain of the receptor, activating the enzymatic activity of the cytoplasmic domain of the receptor (JAK STAT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

receptor tyrosine kinase

A

signal binds to the EC domain of the receptor bound to a tyrosine kinase, which it then activates via phosphorylation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

ion channel

A

signal binds and directly regulates the channel’s opening. electrical potential of membrane is altered

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

GCPRs

A

the signal binds to a cell surface receptor linked to an effector enzyme by a G protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

mechanism of action of GCPR

A

extracellular ligand binds to cell surface receptor, receptor triggered activation of a G protein located on cytoplasmic face of plasma membrane, activated G protein changes activity of effector element, which changes the concentration of intracellular second messenger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

effector elements associated with GPCRs

A

adenylyl cyclase, ion channel, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

intracellular second messengers associated with GPCRs

A

cAMP, Ca2+

26
Q

Gs

A

associated with adenylyl cyclase. s=stimulation, increases levels of cAMP

27
Q

Gi

A

associated with adenylyl cyclase. i=inhibition, decreases levels of cAMP

28
Q

Gq

A

associated with phospholipid C (PLC-beta). stimulatory. increases intracellular calcium levels

29
Q

epinephrine receptor

A

beta adrenergic receptors increase cAMP via Gs

30
Q

acetylcholine receptor

A

muscarinic or nicotinic receptors decrease cAMP via Gi

31
Q

Gq associated with histamine in bronchiolar smooth muscle

A

associated with H1 receptor. increased Ca levels via PLC leads to vessel constriction

32
Q

Gs associated with epinephrine in bronchiolar smooth muscle

A

associated with B2 receptor. increases cAMP levels via adenylyl leading to vessel dilation

33
Q

TxA2 action in platelets

A

goes through Gq pathway in which increased Ca levels lead to platelet aggregation

34
Q

prostaglandin 2 (PGI2) action in platelets

A

goes through Gs pathway in which increased cAMP leads to disaggregation (relaxation)

35
Q

histamine via Gq

A

in bronchiolar smooth muscle cells. leads to contraction (anaphylaxis)

36
Q

histamine via Gs

A

in vascular smooth muscle cells. leads to relaxation/vasodilation

37
Q

GPCR downregulation

A

heterodimerization leading to endocytosis and then recycling or destruction

38
Q

GPCR desensitization

A

response to drugs/agonist diminishes over time.

39
Q

how does desensitization occur?

A

phosphorylation of the serene residues in the GPCR carboxyl tail recruits beta arrestin, which decreases receptor ability to interact with G protein subunit.

40
Q

is desensitization reversible/irreversible?

A

reversible following exposure to more agonist

41
Q

G protein structure

A

heterotrimeric (alpha, beta, gamma). dissociates upon ligand binding

42
Q

therapeutic leverage

A

can target drug action by synthesizing molecule to pick out a specific subtype of receptor

43
Q

graded dose response

A

with increasing dose, there is an increase in response

44
Q

quantal dose response

A

all or none dose response

45
Q

narrow therapeutic index

A

the difference between lethal dose and effective dose is small

46
Q

K3

A

measurement of a drugs intrinsic activity

47
Q

K3=1

A

drug is an agonist

48
Q

K3=0

A

drug is an antagonist

49
Q

1>K3>0

A

drug is a partial agonist

50
Q

threshold dose

A

the dose at which we start seeing a response to the drug

51
Q

Emax

A

the maximal effect of a drug. where it plateaus. if you add any more drug, no further effect will be seen, but toxicity will occur

52
Q

left shifted dose curve

A

indicative of higher potency

53
Q

competitive antagonist

A

involves receptors, completely reversible with increased agonist concentration

54
Q

noncompetitive antagonist

A

involved receptors, agonist fails to reverse it

55
Q

chemical antagonist

A

one drug binds to another drug, inactivating it or blocking its absorption

56
Q

physiologic antagonist

A

one drug does exactly the opposite of another drug and works on a different receptor

57
Q

ED50

A

the median dose required to have effects on 50% of people

58
Q

LD50

A

the median dose required to cause death in 50% of people

59
Q

therapeutic index formula (TI)

A

LD50/ED50

60
Q

what TI makes for a safe drug?

A

> 10/15

61
Q

safety index

A

LD01/ED99

MDTI (42 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions