Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pharm exam 1 > Test 1 > Flashcards

Test 1 Flashcards

1
Q

What are receptors?

A

The component of a cell or organism that interacts with a drug and initiates the chain of events leading to the drug’s observed effects. Most receptors for clinically relevant drugs are proteins

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

Covalent bonds

A

Very strong bonds, in many cases, not reversible under biologic conditions.

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

Electrostatic bonds

A

Weaker than covalent bonds; tend to be much more common than the covalent bonding in drug-receptor interactions.

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

Receptors are responsible for ____

A

selectivity of drug action.

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

What size molecules diffuse more readily between compartments of the body?

A

Smaller molecules, less than 1,000 Da.

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

Lock & Key Phenomenon

A

Drug’s shape is complementary to that of the receptor site

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

Changes in a drug’s _________ can dramatically increase or decrease the molecule’s affinities for different receptors, altering its therapeutic and toxic effects

A

Chemical structure

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

What is chirality?

A

It is not super imposable to its mirror image

-Have the same physical & chemical properties like identical melting points

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

What kind of molecules cross biological barriers by passive diffusion?

A

Uncharged molecules.

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

What is a weak acid?

A

A neutral molecule that can reversibly dissociate into an anion (neg. charged molecule) and a proton (a hydrogen ion)

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

what is a weak base?

A

A neutral molecule that can form a cation by combining with a proton

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

What is pKa

A

The dissociation constant that governs the extent of dissociation when the substance is placed in solution
-an important determinant of how much drug is present in various body fluids.

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

What is a ligand?

A

A molecule that binds to a specific site on a protein or other larger molecules.

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

At least 2 functional domains within the receptor:

A
  • A ligand binding domain

- An effector domain

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

Receptors are:

A 
Regulatory proteins (mainly)
-enzymes, transport proteins, structural proteins, secreted glycoproteins, DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Receptors have at least 2 major functions:

A
  • Ligand binding

- Message propagation

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

Indirect effect-

A

Inhibition of metabolism of endogenous activator –> increased activator action on an effector molecule–> increased effect.

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

How many types of drug receptors are there??

A

five

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

Transmembrane receptor:

A

Regulates intracellular enzyme activity

-Binds & stimulates an intracellular protein kinase

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

Intracellular Receptors

A

Lipid soluble drugs can cross the cell membrane layer & attach to intracellular receptors
-receptor inside the nucleus

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

Glucocorticoid receptor

A

Glucocorticoid binding to its receptor relieves an inhibitory constraint on the transcription-stimulating activity of the protein.
-In the absence of hormone, the receptor is bound to hsp90, a protein that prevents normal folding into the active conformation of the receptor.

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

Nuclear hormone receptor-

A

Agonist and co-activator bind, the co-repressor is released and a conformational change occurs and gene transcription is stimulated. If corepressors are bound, activation does not occur.

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

How fast do gene-active hormones work?

A

lag period of 30 min-several hours.

-this is why you get a longer effect.

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

Ligand-Gated Ion Channels

A

Some drug mimic or block actions of endogenous ligands (e.g. acetylcholine, serotonin, GABA, glutamate) that regulate flow of ions through plasma membrane channels.
Receptor binding causes opening or closing of a channel to regulate the entrance or exit of a specific ion (e.g. Cl-) –
Receptor transmits signal across the plasma membrane by increasing transmembrane conductance of the relevant ion, thus altering the electrical potential across the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Consequence of gated receptors:
Rapid onset and offset of effect The time elapsed between ligand binding to a ligand-gated receptor and the cellular response can often be measured in milliseconds.
26
Transmembrane Receptors
Drug binds to receptor, triggering enzyme reactions – usually a 2nd messenger system (e.g., cAMP) or protein kinases – that result in a change in cell function. ex- epinephrine, norepinephrine, insulin
27
Receptor tyrosine kinases (RTKs)
A family of (transmembrane) receptors The active form of an RTK is phosphorylated at a tyrosine site. Important cancer biomarkers; often important in certain types of human cancer
28
G-Protein Coupled Receptor (GPCR)
- Largest receptor family - Humans express over 800 GPCRs | - Specialized regulatory protein that binds guanosine triphosphate (GTP) and guanosine diphosphate (GDP)
29
GPCRS Regulate-
Sensory perception - nerve activity - tension of smooth muscle - metabolism, rate and force of cardiac contraction - secretion of most glands
30
GPCRS Receptor activators:
- Adrenergic amines - Serotonin - Acetylcholine
31
Drugs Acting at GPCRs
- Drug binds to receptor that is coupled to an intracellular G-protein - Triggering G-protein activity results in activation or inhibition of 2nd messengers or the opening of channels
32
Agonist
Binding mimics effects of endogenous ligands | -some agonists work by inhibiting the mechanism responsible for terminating the action of the endogenous ligand
33
Primary agonist
A drug that binds to the same recognition site as the endogenous ligand
34
Allosteric agonist
A drug that binds to a different region on the receptor
35
Antagonist
Devoid of intrinsic receptor activity - Receptor binding prevents agonist binding, thus preventing the action of agonists and natural ligands - lose receptor function
36
Partial agonists
Bind & activate a given receptor, but have only partial efficacy at the receptor compared to a full agonist, regardless of the concentration employed; they do not evoke as great a response as full agonists. -can display both agonist & antagonist effects, depending on the presence of another agonist.
37
Inverse agonists
binds to the same receptor binding-site as an agonist, but reduces constitutive activity of receptors, exerting the opposite pharmacological effect of a receptor agonist.
38
Constitutive activity
Receptors are active even if nothing is bound to it.
39
A receptor exists exactly 2 conformational states:
- Active | - Inactive
40
Agonists prefer to bind to ____
active receptors
41
which way does an antagonist shift the equilibrium?
- it does not shift the balance | - as long as its sitting there, the agonist can't bind.
42
A drug's action is affected by:
- The quantity of drug that reaches the receptor (pharmacokinetics) - The degree of attraction (affinity) between the drug and its receptor
43
Affinity
The degree of attraction between the drug and its receptor
44
Intrinsic efficacy
Once bound to their receptor, drugs vary in their ability to produce and effect.
45
Both the affinity of a drug for its receptor and its intrinsic efficacy are determined by its __________
Chemical structure
46
What kind of intrinsic efficacy does antagonists have?
-Doesn’t have much intrinsic efficacy because it doesn’t have an effect when bound to the receptor.
47
What kind of intrinsic activity & affinity do agonists have?
Great affinity and intrinsic activity to bind effectively to their receptors and be capable of producing an effect.
48
What are drug effects not produced through receptor interactions?
- colligative effects - chemical interactions - Structural analogs of endogenous chemicals
49
Colligative effect
An effect that depends on the number of solute particles dissolved in a given amount of solvent, not on the chemical natures of the solute or solvent. ex- osmosis -works simply because drug molecule is present
50
neutralization
The reaction of an acid and a base to produce a salt and water
51
Chelation
A method of removing heavy metals from the blood stream. - Chelating agent binds to the metal ion. - can be used for things like poisoning
52
What is a structural analog
A compound having a structure similar to that of another one, but different from it in respect of a certain component. - Body cannot tell the difference - body will try and use it, but it won't work
53
Receptor occupancy theory
-How many receptors are actually bound by the drug at a particular time, the more receptors you bind, the more response you should get.
54
The graded dose response
A little bit of a drug gives a little response, a lot of drug gives a large response.
55
Potency
- The concentration (EC50) or dose (ED50) of a drug required to produce 50% of that drug's maximal effect.
56
Allosteric Activator
Protein or enzyme that binds to its substrate/target, modulates the shape of it and positively influences its activity (or the activity of an agonist)
57
Pharmacodynamic
Occur at the receptor - competitive binding interactions - Noncompetitive binding interactions
58
Pharmacokinetic
result from one drug’s effects on the pharmacokinetics of another
59
Pharmacologic
result from by drugs acting through different mechanisms
60
Quantal dose response relationships
- The all or none response - Threshold dose- the smallest dose that elicits a quantal response - ex- sleeping medication
61
What determines how a drug affects you and how you respond?
Genetic variability
62
Therapeutic index
LD50/ED50 - you want dose to be high - ex of low therapeutic index- anesthesia
63
Standard Safety Margin
LD1/ED99 - ED99- effective dose in 1% of subjects - LD1- lethal dose in 99% of subjects
64
Receptors are subject to many regulatory & homeostatic controls:
- Regulation of receptor synthesis - Regulation of receptor degradation - receptor covalent modification - relocalization within the cell
65
Receptor desensitization
Adaption, down-regulation | -continued or subsequent exposure to the same concentration of drug results in diminished response.
66
Tachyphylaxis
Rapidly diminishing response to successive doses of a drug, rendering it less effective.
67
Receptor down-regulation
A reduction of a cell's response due to internalization and degrading of receptors
68
Intrauterine
Conception to birth
69
Neonate
Brith to 1 month
70
premature neonate
Gestational age
71
Full term neonate
Gestational age >37 weeks, post-natal age
72
Infant
1 month to 2 years
73
child
2 years to the onset of puberty
74
Adolescent
Onset of puberty to adulthood
75
Changes in GI absorption after birth
- In full term infant, gastric pH ranges from 6-8 at birth, then declines to 1-3 within 24 hours - pH gradually returns to neutral agin by day 8 - reaches adult values after 2 years - differences in the bioavailability of drugs in premature infants are poorly understood due to the lack of data
76
77% higher busulifan glutathione conjugation rate in children aged 1-3 years compared to older children (9-17) leads to:
Leads to an enhanced first-pass intestinal metabolism and a reduced bioavailability
77
L-amino acid transporter system
is immature in children and due to that, the oral clearance of drugs is higher, resulting in lower bioavailability
78
P-gp expression in human intestinal tissue...
is relatively low levels in neonates
79
Pgp pump
Drug gets absorbed, pop pump grabs it before going into circulation, and then pushes it back into the intestines ...prevents things from getting absorbed. - Less pgp increases drug absorption - pgp does not affect all drugs
80
Peds: Gastric Emptying and Intestinal Mobility
- Gastric emptying time in neonates is prolonged relative to that of the adult - intestinal motility is irregular in neonates
81
Where is the determinant of the rate of drug absorption from?
The small intestine
82
Gastric Emptying & Intestinal Motility:clinical complications
- Rate of drug absorption is slower in neonates, young infants - Delayed gastric emptying may partially account for delayed absorption for orally administered drugs - Time required to achieve Cmax may be prolonged - Overall bioavailability may be altered - drugs with limited absorption in adults may be absorbed efficiently in neonates because of prolonged contract time with GI mucosa
83
Cmax
Peak concentration
84
Intramuscular absorption may be altered in premature infants due to differences in:
- Relative muscle mass - Poor perfusion to various muscles - Peripheral vasomotor instability - Insufficient muscular contractions compared to older children nd adults - intramuscular dosing is rarely used in neonates except in emergencies or when an intravenous site is inaccessible.
85
Integumentary system in babies
- Thickness in pre term babies is a lot thinner - Hydration of skin is reduced overtime in age - Body surface area:weight slow declines with age
86
How would you expect the apparent Vd of water soluble drugs?
volume of distribution is lower later in life
87
How would you expect the apparent Vd of lipid soluble drugs
volume of distribution is higher later in life, because there is less fat.

Pharm exam 1 (1 decks)

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