Brainscape's Knowledge GenomeTM

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


See full index

BMS 242 Core Physiology and Pharmacology > Receptors I > Flashcards

Receptors I Flashcards

1
Q

What drug type creates a response in the cell

A

agonist

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

What is occupation of a drug-receptor governed by?

A

Affinity

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

What is activation of a drug-receptor governed by?

A

efficacy

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

What part of a drug receptor reaction is reversible

A

occupation forming a complex

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

What is the ratio of reversibility of a drug receptor reaction governed by?

A

affinity of the drug

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

Describe the reversibility of drugs with high affinities

A

slow reversibility

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

Describe occupancy

A

proportion of receptors occupied will vary with the drug concentration

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

What does occupancy vary between

A

0 and 1

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

How much drug is present at 0 occupancy

A

none

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

How can we measure occupancy

A

by measuring response

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

Describe the relationship between occupancy and response

A

high occupancy means there is a large response

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

Can you measure antagonists activity using occupancy

A

NO

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

Examples of ligands

A

neurotransmitters, hormones, growth factors, cytokines, drugs, toxins

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

Examples of protein targets

A

receptors, ion channels, enzymes, transporters

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

Describe a ligand binding practical

A

tissue prep with radio-ligand, incubation, filtration, rinse, count, data analysis

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

True or False - most ligands bind non-specifically to tissue, filter paper, glass

A

TRUE

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

How can non-specific ligand binding be reduced

A

reduced by anti-absorbants

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

What are some examples of anti-absorbants

A

albumin, collagen, o-catechol

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

What is the function of rinsing in a ligand binding practical

A

remove unbound radioligand from incubation medium

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

What is a key measurement in receptor ligand assays

A

specific and non specific binding

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

What are the disadvantages of using a radio ligand

A

degradation

22
Q

How can you prevent degradation of radio ligands

A

free radical scavenger, store at low temp, avoid light, incorporation of antioxidant

23
Q

What are radio ligands labelled with

A

radio active labels

24
Q

Name two radio labels

A

tritum, iodine

25
Q

What are the disadvantages of tritum

A

specialised labs required, expensive

26
Q

What are the advantages of tritum as a label

A

high specific activities, good stability, long half life

27
Q

What are the advantages of iodine as a label

A

easy and cheap, if aromatic hydroxyl group can be incorporated at high specific activities

28
Q

What are the disadvantages of iodine

A

more readily degraded, short half life, activity of ligand can be reduced

29
Q

What tissue would you select for your ligand binding practical

A

tissue that contains the receptors of interest

30
Q

What can the tissue be in the ligand binding practical

A

isolated membranes, slices, synaptosomes, purified receptors

31
Q

What must incubation preserve

A

integrity of ligands and binding sites

32
Q

What happens during the tissue incubation period of the ligand binding practical

A

enzymes are liberated

33
Q

What is the effect of enzymes being liberated during the tissue incubation period

A

enzymes break down receptors of interest

34
Q

What are the enzymes liberated during the tissue incubation period

A

proteases

35
Q

How can the effect of enzymes be minimised during the tissue incubation period

A

protease inhibitors added for peptides, anti-oxidants if ligand is oxidisable

36
Q

What is the temperature during the incubation period

A

low room temperature to 0 degrees

37
Q

How is the tissue and bound ligand separated from free ligand

A

filtration or centrifugation

38
Q

What is a problem when separating bound ligand from free ligand during the practical

A

rate of dissociation of ligand-receptor complex

39
Q

What must speed of separation of bound ligand from free ligand be compatible with

A

affinity of ligand for receptor

40
Q

What type of separation does lower affinity of ligand receptor require

A

faster/more efficient separation

41
Q

How do you work out specific binding

A

subtract non specific binding from total bound

42
Q

How is ligand receptor binding data plotted

A

semi-logarithmic scale

43
Q

What is saturable binding

A

specific binding

44
Q

Why is radio-ligand binding saturable

A

total number of receptors is limited

45
Q

What does the Langmuir equation describe

A

relationship between receptor occupancy, affinity and drug concentration

46
Q

What is Bmax in the Scatchard equation

A

maximum amount of drug which can bind specifically to receptors

47
Q

What is F in the Scatchard equation

A

free ligand concentration

48
Q

What is KD in the scatchard equation

A

dissociation constant for radio ligand

49
Q

What determines the dissociation constant for the radio ligand

A

saturation analysis

50
Q

What is KD a measure of

A

affinity

51
Q

What does high KD show

A

low affinity

BMS 242 Core Physiology and Pharmacology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions