Brainscape's Knowledge GenomeTM

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


See full index

Pharmacology > Exam 1 Ch 2 & 3 Drug Receptors & Pharmacodynamics > Flashcards

Exam 1 Ch 2 & 3 Drug Receptors & Pharmacodynamics Flashcards

1
Q

What is tachyphylaxis?

A

When responsiveness diminishes rapidly after administration of a drug

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

What is one major mechanism by which tumor cells develop resistance to anti-cancer drugs?

A

Up-regulation of multidrug resistance (MDR) gene-enconded transporter expression

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

What is a target molecule in the biologic system that plays a regulatory role and interacts with a drugs and initiates a chain of events leading to drug’s observed effects?

A

Receptor

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

What is any substance that brings about a change in biologic function through its chemical actions?

A

Drug

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

What are the three things that receptors generally do?

A
  1. Determine the quantitative relation between dose or concentration of drug and pharmacologic effects through receptor affinity and total number of receptors.
  2. Responsible for selectivity of drug action due to molecular size, shape, and electrical charge of drug
  3. Mediate the actions of pharmacologic agonists and antagonists
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

List the type of drug receptors.

A 
Transport Proteins
Orphan receptors
Regulatory proteins
Structural Proteins
Enzymes

Mnemonic: TORSE

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

What do regulatory protein drug receptors do?

A

Mediate actions of endogenous ligands

Ex: Neurotransmitters, hormones

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

What is an example of enzyme drug receptors?

A

Dihydrofolate reductase is the receptor for the antineoplastic dug methotrexate

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

What is an example of a transport protein drug receptor?

A

Na+/K+ - ATPase is a membrane receptor for cardioactive digitalis glycosides

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

what is an example of a structural protein drug receptor?

A

Tubulin is the receptor for colchicine, which is an anti-inflammatory agent

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

What is an example of an orphan drug receptor?

A

Ligands presently unknown

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

What is an agonist?

A

A compound that binds to a receptor and produces the biologic response by activating the receptor

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

What is an antagonist?

A

A compound that binds to a receptor, but does not activate generation of a signal. It also interferes with the agonist’s ability to activate the receptor. They do not have any effect on their own.

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

What is a Physiologic Antagonist?

A

A drug that counters the effects of another by binding to a different receptor and causing opposing effects

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

What is a Chemical Antagonist?

A

A drug that counters the effects of another by binding the agonist drug (not the receptor)

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

What is a Competitive Antagonist?

A

Maximal effect reached, but at higher does of agonist

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

What is a Non-competitive antagonist?

A

Reduced maximal effect even at high doses

It is irreversible and allosteric

18
Q

What does a partial agonist produce?

A

Produces that biologic response but cannot produces 100% of he response even at high does

19
Q

What does the Inverse agonist do?

A

Have the opposite effects form a full agonist.

Decrease the effects of the receptor

20
Q

What does coupling mean when talking about drugs?

A

Overall transduction process that links drug occupancy of receptors and pharmacologic response

21
Q

What are spare receptors?

A

AKA receptor reserve
Receptors are saidn to be “spare” for a given pharmacologic response if it is possible to elicit a maximal biology response at a concentration of agonist that does not result in occupancy of all of the available receptors

22
Q

What happens after an agonist occupies a receptor?

A

A conformational change in the receptor protein occurs

23
Q

When an agonist occupies a receptor, a conformational change in receptor protein occurs. What happens next?

A

Receptor Activation occurs

24
Q

When an agonist occupies a receptor, a conformational change in a receptor protein occurs, which results in receptor activation. What does this process start?

A

The beginning of many steps to produce biologic response.

25
Q

List the types of transmembrane receptors

A 
Intracellular receptors
Cytokine Receptors
Enzyme-Linked Receptors
Ligand-gated ion Channels
G-protein Coupled Receptors

Mnemonic: ICE LG

26
Q

How do Intracellular Receptors work?

A

A lipid-soluble chemical signal crosses the plasma membrane and acts on an intracellular receptor (which may be an enzyme or a regulator of gene transcription)

27
Q

How do Enzyme-Linked Receptors work?

A

The signal binds to the extracellular domain of a transmembrane protein, thereby activating an enzymatic activity of its cytoplasmic domain

28
Q

How do Cytokine Receptors work?

A

The signal binds to the extracellular domain of a transmembrane receptor bound to a separate protein tyrosine kinase, which it activates

29
Q

How do Ligand gated ion channels work?

A

The signal binds to and directly regulates the opening of an ion channel

30
Q

How do G-protein Coupled Receptors work?

A

The signal binds to a cell-surface receptor linked to an effector enzyme by a G protein. The transmembrane receptor protein that stimulates a GTP-binding signal transducer protein (G protein), which in turn modulates production of an intracellular second messenger.

31
Q

Intracellular receptors for lipid-soluble agents are known to be what kind of receptors?

A

Gene-active receptors

32
Q

List 2 examples of lipid-soluble ligands that would bind to an intracellular receptor.

A

Steroids

Thyroid Hormone

33
Q

What is the therapeutic significance of an intracellular receptor for lipid-soluble agent?

A

Slower onset of action

Longer duration of action

34
Q

Describe the ligand-receptor transmembrane enzyme domains.

A

There are 2 domains that are connected by a hydrophobic segment of polypeptide that crosses plasma membrane.
One domain is extracellular hormone-binding domain. This domains ligands include insulin, EGF, PDGF, ANP, and TGF-Beta.
The other domain is a cytoplasmic enzyme domain that my be a protein tyrosine kinase, a serine kinase, or a guanylyl cyclase.

35
Q

What occurs during downregulation? How do you get downregulation? What is an example?

A

The ligand binding triggers accelerated endocytosis of receptors from cell surface. The receptors and bound ligands are degraded. When this process occurs at a faster rate than de novo synthesis of receptors, you get downregulation. The cell’s responsiveness to the ligand is diminished.
EX: EGF receptor tyrosine kinase

36
Q

What do cytokine receptors respond to?

A

Respond to heterogenrous group of peptide ligands like growth hormone, erythropoietin, interferons, etc.

37
Q

What are cytokine receptors similar to and why is it different?

A

Very similar to receptor tyrosine kinases
Protein tyrosine kinase activity is not intrinsic to this receptor molecule, meaning it does not have intrinsic enzymatic activity.

38
Q

Cytokine receptors have separate protein tyrosine kinase from what family and has what kind of binding?

A

Separate protein tyrosine kinase from the Janus-kinase (JAK) family binds noncovalently to the receptor

39
Q

What do ligand and voltage-gated ion channels regulate?

A

Regulate the flow of ions through plasma membrane

40
Q

Describe the voltage-gated ion channels. Give examples.

A

Do not bind neurotransmitter directly
Controlled by membrane potential
EX: Verapamil inhibits voltage-gated calcium channels in the heart and vascular smooth muscle. It is a calcium channel blocker.

41
Q

Describe the Ligand-gated Channel. Give an example of a ligand-gated channel.

A

Increased transmembrane conductance of the relevant ion thus altering electrical potential across the membrane
Ex: Acetylcholine binding to nicotonic acetylcholine receptor (nAChR) allows Na+ to flow down concentration gradient into cells causing deplorarization.

42
Q

Name some examples of ligands for the ligand-gated ion channels. What kind of ligands are the examples?

A

Endogenous ligands include:

Acetylcholine, serotonin, GABA, and glutamate

Pharmacology (12 decks)

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