Brainscape's Knowledge GenomeTM

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


See full index

MTP > Exam 2: Receptors and Drug-Receptor Interactions > Flashcards

Exam 2: Receptors and Drug-Receptor Interactions Flashcards

1
Q

Is a receptor stereometric?

A

No, receptor does not have an enantiomer of itself therefore it’s static

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

What is stereoiosomerism?

A

A carbon atom with 4 different substituents that doesn’t posses a plane or point of symmetry

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

What make a molecule symetrical?

A

Carbon contains 2 or more of the same substituents of a plane or point of symmetry

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

How are the substituents of a carbon sorted?

A

From highest to lowest molecular weights

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

What are enantiomers?

A

Nonsuperimposible molecules that are mirror images

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

Identify the relationship of these 2 molecules

A

Enantiomers

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

Identify the relationship of these 2 molecules

A

Enantiomers

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

Identify the relationship of these 2 molecules

A

Enantiomers

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

What are diastereomers?

A

Nonsuperimposible molecules that have the same molecular formula however are not mirror images

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

Identify the relationship of these 2 molecules

A

Diastereomers

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

Identify the relationship of these 2 molecules

A

Diastereomers

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

What are E-Z isomers?

A

Pertains to alkene carbons

E: high and low priority groups on both sides

Z: same priority group on either sides

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

Identify the relationship of these 2 molecules

A

E-Z isomers

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

Define occupancy theory

A

The prediction of a response that is related to the number of receptors are bound by an agonist

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

According to the occupancy theory, how do we create a greater response?

A

Having more drugs bound to the receptor to where receptors become saturated

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

What is the rate theory?

A

The number of drug-receptor interactions per unit time determines the intensity of the response

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

According to rate theory, how do we create a greater response?

A

Drugs that associate with then rapidly dissociate from the receptor, allowing another drug molecule to interact with the receptor

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

What is the induced-fit theory?

A

The drug approached the receptor a conformational change occurs in the receptor to allow for effective binding

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

Describe the shape of a receptor in regards to induced-fit?

A

Receptor does not normally exist in the proper conformation for drug binding, when a drug dissociates the the receptor revert to its original form

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

What is macromolecular perturbation theory?

A

Suggests that 2 types of conformational changes exist and the rate of their existence determine the observed biological response

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

What are the conformational changes that occur for macromolecular perturbation theory?

A
  1. Agonist produces a specific form for biological response
  2. Antagonist produce non-specific forms that fails to produce a response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is activation-aggregation theory?

A

Receptors are always at equilibrium between active and inactive forms

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

How does agonists and antagonist shift equilibrium?

A

Agonists: Shift it towards active state

Antagonists: shift it towards inactive states

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

How does a drug-receptor complex form?

A

The solvent molecule on the receptor is displaced by drug to produce a solvated complex

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

What make a solvated complex effective?

A

Interactions between drug and receptor must be stronger than interactions with the solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why are drug-receptor complex formation entropically unfavored?

A
  1. Causes a loss in conformational degrees of freedom form ligands and proteins
  2. Causes a loss of 3 rotational and 3 translations degrees of freedom
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How do drug-receptor complexes compensate for being entropically unfavored?

A

Highly favorable enthalpic interactions between drug and receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What bond is considered a strong bond?

A

Covalent due to its irreversibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What makes a drug inactivate?

A

When the concentration in the extracellular fluid decreases, drug-receptor binding are irreversible due to weak non-covalent interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Why is it important for drugs to be irreversible?

A

Desired drugs are predictable and pharmacological action can be terminated after a limited time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

In what cases are drugs irreversible?

A
  1. Chemo to kill tumor cells
  2. Antibiotics to kill bacteria
32
Q

What is a covalent bond?

A

A chemical bond formed by sharing a pair of electrons (suicide inhibitors)

33
Q

What are ionic interactions?

A

Drug and receptor groups will be mutually attracted provided they have opposite charge

34
Q

What makes an ionic interaction beneficial?

A

Effective at further distances compared of IM forces

35
Q

What makes a dipole weaker than an ion?

A

Dipole charge is less than an ion

36
Q

What is a hydrogen bond?

A

Formed between the H+ and an electronegative atom (SNO)

37
Q

What is the difference between inter and intramolecular bonds?

A

Inter: interactions between 2 molecules

Intra: interactions in a single molecule

38
Q

What is a charge-transfer complexes?

A

When a molecule that is a good electron donor comes into contact with a molecule that is a good electron acceptor, the donor may transfer some of its charge to the acceptor creating a molecular dipole-dipole interactions

39
Q

What type of molecules can achieve charge-transfer complexes?

A

Donor groups containing pi electrons

40
Q

What are hydrophobic interactions?

A

When water molecules orient themselves around the molecule and are in a higher energy state in the presence of a nonpolar region of molecule

41
Q

What is the behavior of 2 nonpolar molecules in contact?

A

Nonpolor dissolve together (not attracted) by their decrease in free energy due to the increased entropy of water molecules

42
Q

What are van der waals?

A

Non polar molecules that have a temporary nonsymmetrical distribution of electron density (temporary dipole)

43
Q

What make a van der waal weak?

A

Only significant when there is a close surface contact of atoms

44
Q

Identify the potential interactions of the drug

A

A: Hydrophobic

B: H-bond

C: Ion or ion-dipole

D: Hydrophobic

E: Hydrophobic

F: Dipole-dipole or H-bond

G: Hydrophobic

H: Charge-transfer or H-bond

45
Q

What is spatial arrangement?

A

The location of functional groups about their molecular scaffold and their proximity to thei interaction site within the receptor

46
Q

What is a pharmacophore?

A

The minimum structural requirements of a molecule that will be recognized by a receptor and possess a specific activity

47
Q

What make antihistamine molecules similar?

A

They have specific binding sites on the H1 receptor that have an appropriate topography for interactions with certain groups

48
Q

What make an antihistamine different from a histamine molecule?

A

It is an H1 antagonist containing a tertiary amino group what will is protonated at physiological pH creating an ionic bond between drug and receptor

49
Q

Describe how two enantiomers become diasteriomers when bound to a receptor?

A

Receptors are static and molecule will have different binding properties

50
Q

What configuration do all human amino acids come in?

A

L

51
Q

In what ways do enantiomeric drugs have varying degrees of activity?

A
  1. One enantiomer may possess activity while the other might be completely inactive
  2. Both enantiomer may have equal effect
  3. Most often, both enantiomer will demonstrate some activity with one enantiomer demonstrating activity to a much higher degree
52
Q

What is an eutomer?

A

The more potent isomer

53
Q

What is a distomer?

A

The less potent isomer

54
Q

What is a eudismic ratio?

A

The ratio of more potent (higher affintiy) enantiomer to the less potent enantiomer

55
Q

What type of enantiomer has the highest degree of receptor complementary?

A

Highly potent antagonist

56
Q

When are high eudismic ratio observed?

A

In stereoisomers typically found in antagonists because receptors can not hold distomers

57
Q

When are low eudismic rations observed?

A

When eutomer has a lower affinity for the receptor or when the stereogenic centers lies outside the region of critical receptor binding

58
Q

What are isomeric ballast?

A

Distomer that are considered as an impurity in a mixture that can contribute to adverse reactions

59
Q

What are the dangers of racemic mixtures?

A

One enantiomer may antagonize the other and no effect will be observed

60
Q

What is a hybrid drug?

A

A type of compound with 2 separate mechanisms of action and therapeutic activities

61
Q

What are psedo-hybrid drugs?

A

When multiple isomeric forms are involved in the biological activity

62
Q

What are the stereoisomeric forms?

A

RR, SS, RS, SR

63
Q

What are RR isomers of antihypertensives used for?

A

Beta-blocking activity

64
Q

What are SR isomers of antihypertensives used for?

A

Alpha-blocking activity

65
Q

What are SS and RS of antihypertensive used for?

A

Completely inactive, the isomeric ballast

66
Q

Why are isomeric ballast not typically removed for economic reasons?

A
  1. Separation of enantiomers is very difficult and time consuming
  2. Separation of all isomers lowers the overall yield of the active component
67
Q

What is a racemic switch?

A

A single-entity drug of one enantiomer

68
Q

What are the advantages of single isomers?

A
  1. Lower effects and toxicity
  2. Half of racemate dose to achieve maximum therapeutic effect
  3. Can increased the dose of purified racemate if max effect was not observed
69
Q

What are the disadvantages of single isomers?

A
  1. Dosing a single enantiomer can cause unobserved side effect that other enantiomer was masking
  2. Can cause a lower effect than expected from the racemate
70
Q

What does this picture indicate?

A

Enantiomeric binding selectivity

71
Q

What makes drug more potent?

A

The more bonds its able to make with the receptor

72
Q

What does this picture tell you about the drug?

A

The E form is more potent than the Z form because its ability to bind to the receptor. E is the eutomers.

73
Q

What are rotamers?

A

A set of isomeric conformers of a drug molecule

74
Q

What are bioactive conformation?

A

A receptor may bind only one of the conformers

75
Q

What makes a conformational isomer?

A
  1. Free rotation about single bonds providing conformational flexibility
  2. Variety of conformations in space without breakage of bonds
76
Q

What is the favorable conformational isomer (bioactive conformation)?

A

The molecule that exists in its lowest energy state

77
Q

What can prevent molecules from assuming their lowest energy state?

A

Intramolecule h bond

MTP (15 decks)

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