Brainscape's Knowledge GenomeTM

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


See full index

AY Principles > Pharmacology > Flashcards

Pharmacology Flashcards

1
Q

What is an agonist?

A

A drug that binds to a receptor o produce a cellular/biological response

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

What is an antagonist?

A

A drug that blocks the actions of an agonists

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

What is efficacy?

A

The ability of an agonist to ellicit a response

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

What is affinity?

A

The strength of association between ligand and receptor

Longer the against stays on the receptor the higher the affinity

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

What shape is the relationship between concentration and response of a drug?

A

Sigmoidal

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

What happens to curve in presence of competitive antagonist?

A

SHIFTED PARALLEL TO THE RIGHT
Slope remains the same shape
Max remains the same
EC50 is increased

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

What happens to the curve in presence of non competitive antagonist?

A

POSITION OF CURVE STAYS THE SAMENESS
Slope is decreased
Max response is decreased
EC50 is unchanged

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

Examples of regulatory proteins that drugs bind to?

A 
Enzymes 
Carrier molecules 
Ion channels 
Receptors 
(DNA or RNA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the distribution of a drug?

A

The process by which it leaves the circulation and enters the tissues

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

What is the metabolism of a drug?

A

Process by which tissue enzymes (principally in the liver) catalyse the chemical conversion of a drug to a more polar form that is easily excreted from the body

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

How do drugs get from the stomach & intestines to the liver?

A

Portal circulation

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

What physiochemical factors affect drug absorption?

A

Solubility
Chemical stBilty
Lipid to water partition coefficient
Degree of ionisation

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

Do acidic drugs become more or less ionised in a acidic environment?

A

Less

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

What factors affect GI absorption of drugs?

A 
GI motility 
pH at the absorption site 
Blood flow to the stomach & intestines (increased by food) 
Way in which capsule is manufactured 
Physics chemical interactions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Downsides of taking medication orally?

A

Inactivation of some drugs by acids/enzymes
Variable absorption
First pass metabolism
GI irritation

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

How do you calculate the volume of distribution of a drug?

A

Vd = dose(mass) / plasma concentration

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

What is the somatic afferent nervous system?

A

Nerves that supply skin, joints & muscles

Send info to CNS

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

What is the somatic efferent nervous system?

A

Includes neurons that leave spinal cord and enervate muscle (voluntary contraction)

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

What is the enteric nervous system?

A

In walls of GI tract
Involves nerves of the myenteric plexus and submucosa plexus
“Little brain of the gut”

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

Functions of the ANS

A

Contraction and relaxation of vascular and visceral smooth muscle
All exocrine and certain endocrine secretions
The heart beat
Aspects of metabolism
Training allows degree of control of some ANS functionsn(e,g, urination/deflection)

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

What is a ganglion?

A

A collection of nerve cell bodies that lies outside the CNS.nthey lie in different positions depending on whether they’re sympathetic or parasympathetic

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

What neurotransmitters does the sympathetic system use?

A 
Acetylcholine = preganglionic 
Noradrenaline = postganglionic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Difference between pre and para vertebral ganglia?

A 
Paravertebral = close to spinal cord
Prevertebral = further away from spinal cord
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Why is adrenal gland the exception in ganglions?

A

Pre ganglionic innervation but transmitter is Ach

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

What neurotransmitter does parasympathetic system use?

A

Acetyl choline

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

Where are parasympathetic ganglia found?

A

Mainly in the target organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Difference between efferent and afferent signals?

A 
Efferent = away from the CNS 
Afferent = towards the CNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What cranial nerves are involved in the parasympathetic outflow?

A

3, 7, 9 & 10

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

Sympathetic actions on the heart

A

Increases HR

Increases force of contraction

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

Parasympathetic actions on the heart

A

Decreases HR

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

Sympathetic actions on the lungs

A 
Relaxes bronchi (via release of adrenaline)
Decreases mucus production (decreased airway resistance)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Parasympathetic actions on the lung

A

Constricts bronchi

Stimulates mucus production (increased airway resistance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Sympathetic actions on the intestines

A

Reduces motility

Contradicts sphincters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Parasympathetic actions on the intestines

A

Increases motility

Relaxes sphincters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Mechanism of cholinergic transmission

A

1- Uptake of choline via transporter
2- Synthesis of ACh via choline acetyltransferase (CAT)
3 - Storage of ACh via transporter (concentrates)
4 - Depolazization by action potential
5 - Ca2+ influx through voltage-activated Ca2+ channels
6 - Ca2+- induced release of ACh (exocytosis)
7 - Activation of ACh receptors (nicotinic or muscarinic) causing cellular response
8 - Degradation of ACh to choline and acetate by acetylcholinesterase (AChE) – terminates transmission
9 - Reuptake and reuse of choline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Two types of signal in cholinergic transmission

A

Electrical signal from transmitted gated ion channels

Biochemical signal from G protein coupled receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Why activates G-protein-coupled muscarinic acetylcholine receptors in parasympathetic division

A

ACh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What drug block ganglionic transmission no what is its mechanism of action

A

Hexamethonium

Open channel block - form of non competitive antagonism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Examples of G protein coupled receptor

A

Muscarinic ACh receptor

40
Q

Is signalling via G-proteins fast or slow when compared to transmitter gated ion channels?

A

Slow

41
Q

Structure of G protein

A

Peripheral membranes protein
3 polypeptide subunits
(a, B & y - B & y always join together - “beta gamma complex”)
Guanine nucleotide binding site in alpha subunit
Can hold GTP & GDP

42
Q

How to G-protein coupled receptors work when they are not signalling?

A

Receptor is unoccupied
Alpha subunit binds GDP
Th effector is not modulated

43
Q

How do G-protein coupled receptors work to turn on the signal?

A

Agonist activates receptor
G protein couple with receptor causing a conformational change - reducing the affinity of the binding site for GDP
GDP dissociates from, and GTP binds to the alpha subunit
(Guanine nucleotide exchange)

G-protein loses affinity for “beta gamma complex” therefore it dissociates into different a & By subunits
G protein alpha subunits combines with and modifies activity of effector (effector is modulated)

44
Q

What happens of the agonist dissociates from the receptor

A

Signalling still persists

45
Q

How is the signal turned off in G-protein coupled receptor signalling?

A

Alpha subunit acts as enzyme to hydrolyse GTP to GDP and Pi.
This turns the signal off
G-protein regains its affinity for By subunit and alpha subunit recombined with the By subunit completing the G protein cycle

46
Q

Which alpha sub unit couples with M1 receptors?

A

Gq

47
Q

Example of where M1 receptors found and what do they do?

A

M1 receptors in stomach cause acid secretion

48
Q

Which subunit do M2 couple with?

A

Gi (inhibitors)

49
Q

Example of where M2 receptors are found and what they do?

A

On the SA node - thus can decrease the rate of cardiac contraction when stimulated by parasympathetic neurones

50
Q

Which alpha subunit do M3 receptors couple to?

A

Gq

51
Q

In general what do U1 and U2 do?

A

Reuptake of NA in adrenoceptors

52
Q

What does U1 do?

A

NA can either be repackaged into vesicles or it can be degraded to inactive metabolites by MAO enzyme. MAO is the target of some anti-depressive drugs.

53
Q

Therapeutic importance of U2

A

Noradrenaline broken down by COMT

54
Q

What receptor does Gs couple with?

A

Beta-1 - sympathetic stimulation of the heart is dependent on beta-1 receptors and stimulation of adenylyl cyclase

Beta-2 - vascular smooth muscle that supplies skeletal muscle - when adrenaline is release during exercise it binds to B-2 adrenoreceptors in muscle. Increasing the perfusion of blood vessels in muscle

55
Q

Summary of how Gs and B1 work?

A

B1 and Gs bind
Stimulate adenylyl cyclase
Increase heart rate and force

56
Q

Summary of how B2 and Gs work?

A

B2 and Gs bind
Stimulation of adenylyl cyclase
Relaxation of bronchial and vascular smooth muscle

57
Q

What does Gq bind to?

A

Alpha-1 - when noradrenaline is released from a post ganglionic nerve for most types of vascular smooth muscle it causes contraction

58
Q

Summary of how Gq and A1 work?

A

Gq and A1 bind
Stimulation of phospholipase c
Contraction of vascular smooth muscle

59
Q

What does Gi bind to?

A

Alpha-2

60
Q

Summary of how GI and A2 work?

A

A2 and Gi bind
Inhibition of adenylyl cyclase
Inhibition of NA release

61
Q

What happens in presynaptic heteroreceptors?

A

In organs supplied by both sympathetic and parasympathetic nervous systems they communication and mutual antagonism occurs

Sympathetic down regulates the activity of the paradympathetic

62
Q

What happens in presynaptic autoreceptors?

A

ACh released - limits Ca influx - limits ACh release (negative feedback)

NA released - binds to a2 - less Ca in - less NA release (neg feedback)

63
Q

What is the action of cocaine on the ANS?

A

Similar structure to NA
Binds to U1 and prevents uptake of NA
Higher conc of NA in synaptic cleft
Leads to more stimulation of post-synaptic neurone

Peripheral actions cause vasoconstriction (a1 stimulation)
causes cardiac arrhythmias (B1 stimulation)

64
Q

Actions of amphetamine on the ANS

A

Resembles NA
Inhibits MAO enzymes
Amphetamine is imported into the vesicle
Displaces NA into the cytoplasm
Conc of NA builds up in the synapse cleft causing incredd eerie ocelots stimulation

Peripheral actions cause vasoconstriction (a1 stimulation) 
cardiac arrhythmias (B1 stimulation)
65
Q

Actions of prazosin on the ANS?

A

Selective, competitive antagonist of a1 (vascular smooth muscle)
Does not block a2, B1 or B2
Vasodilator used as anti-hypertensive agent
Causes relaxation of vascular smooth muscle - vasodilator

66
Q

Actions of atenolol on the ANS?

A

Selective, competitive antagonist if B1
Dos not block B2, a1 or a2
Used as anti angina, and anti-hypertensive agent

67
Q

Actions of salbutamol on the ANS

A

Selective B2 agonist
Does not activate B1, a1 or a2
Bronchodilator used in asthma

68
Q

Actions of atropine on the ANS

A

Competitive antagonist of muscarinic ACh receptors
Does not block nicotinic ACh receptors
Blocks all muscarinic ACh receptors with equal affinity (1,2,3)
Exerts widespread blockade on parasympathetic division of the ANS

Used to reverse bradycardia after an MI

69
Q

What is the half life of a drug?

A

The time taken for the conc to fall by 50%

Inversely related to the elimination constant

70
Q

What is clearance?

A

The theoretical volume of a fluid (e.g. plasma) from which a drug is totally removed in unit time

71
Q

Which alpha sub unit couples with M1 receptors?

A

Gq

72
Q

Example of where M1 receptors found and what do they do?

A

M1 receptors in stomach cause acid secretion

73
Q

Which subunit do M2 couple with?

A

Gi (inhibitors)

74
Q

Example of where M2 receptors are found and what they do?

A

On the SA node - thus can decrease the rate of cardiac contraction when stimulated by parasympathetic neurones

75
Q

Which alpha subunit do M3 receptors couple to?

A

Gq

76
Q

In general what do U1 and U2 do?

A

Reuptake of NA in adrenoceptors

77
Q

What does U1 do?

A

NA can either be repackaged into vesicles or it can be degraded to inactive metabolites by MAO enzyme. MAO is the target of some anti-depressive drugs.

78
Q

Therapeutic importance of U2

A

Noradrenaline broken down by COMT

79
Q

What receptor does Gs couple with?

A

Beta-1 - sympathetic stimulation of the heart is dependent on beta-1 receptors and stimulation of adenylyl cyclase

Beta-2 - vascular smooth muscle that supplies skeletal muscle - when adrenaline is release during exercise it binds to B-2 adrenoreceptors in muscle. Increasing the perfusion of blood vessels in muscle

80
Q

Summary of how Gs and B1 work?

A

B1 and Gs bind
Stimulate adenylyl cyclase
Increase heart rate and force

81
Q

Summary of how B2 and Gs work?

A

B2 and Gs bind
Stimulation of adenylyl cyclase
Relaxation of bronchial and vascular smooth muscle

82
Q

What does Gq bind to?

A

Alpha-1 - when noradrenaline is released from a post ganglionic nerve for most types of vascular smooth muscle it causes contraction

83
Q

Summary of how Gq and A1 work?

A

Gq and A1 bind
Stimulation of phospholipase c
Contraction of vascular smooth muscle

84
Q

What does Gi bind to?

A

Alpha-2

85
Q

Summary of how GI and A2 work?

A

A2 and Gi bind
Inhibition of adenylyl cyclase
Inhibition of NA release

86
Q

What happens in presynaptic heteroreceptors?

A

In organs supplied by both sympathetic and parasympathetic nervous systems they communication and mutual antagonism occurs

Sympathetic down regulates the activity of the paradympathetic

87
Q

What happens in presynaptic autoreceptors?

A

ACh released - limits Ca influx - limits ACh release (negative feedback)

NA released - binds to a2 - less Ca in - less NA release (neg feedback)

88
Q

What is the action of cocaine on the ANS?

A

Similar structure to NA
Binds to U1 and prevents uptake of NA
Higher conc of NA in synaptic cleft
Leads to more stimulation of post-synaptic neurone

Peripheral actions cause vasoconstriction (a1 stimulation)
causes cardiac arrhythmias (B1 stimulation)

89
Q

Actions of amphetamine on the ANS

A

Resembles NA
Inhibits MAO enzymes
Amphetamine is imported into the vesicle
Displaces NA into the cytoplasm
Conc of NA builds up in the synapse cleft causing incredd eerie ocelots stimulation

Peripheral actions cause vasoconstriction (a1 stimulation) 
cardiac arrhythmias (B1 stimulation)
90
Q

Actions of prazosin on the ANS?

A

Selective, competitive antagonist of a1 (vascular smooth muscle)
Does not block a2, B1 or B2
Vasodilator used as anti-hypertensive agent
Causes relaxation of vascular smooth muscle - vasodilator

91
Q

Actions of atenolol on the ANS?

A

Selective, competitive antagonist if B1
Dos not block B2, a1 or a2
Used as anti angina, and anti-hypertensive agent

92
Q

Actions of salbutamol on the ANS

A

Selective B2 agonist
Does not activate B1, a1 or a2
Bronchodilator used in asthma

93
Q

Actions of atropine on the ANS

A

Competitive antagonist of muscarinic ACh receptors
Does not block nicotinic ACh receptors
Blocks all muscarinic ACh receptors with equal affinity (1,2,3)
Exerts widespread blockade on parasympathetic division of the ANS

Used to reverse bradycardia after an MI

94
Q

What is the half life of a drug?

A

The time taken for the conc to fall by 50%

Inversely related to the elimination constant

95
Q

What is clearance?

A

The theoretical volume of a fluid (e.g. plasma) from which a drug is totally removed in unit time

AY Principles (11 decks)

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