Pharmacodynamics

Question 1

Pharmacodynamics

Answer 1

Effect of a drug on the body

based on the concept of drug receptor binding

Question 2

Affinity

Answer 2

Kd
D+R <-> DR

Kd= disassociation constant
1. Ratio of rate at which the drug binds to the receptor compared to the rate that a receptor complex disassociates
2. As drug concentration increases the concentration of bound receptors increases and as free receptors inc, bound receptors concentration inc as well

Question 3

Dose response relationship

Answer 3

certain doses are associated with certain responses

Question 4

Potency (EC50)

Answer 4

amount of drug that produces a response in 50% of the population

more potent needs lower dose

Question 5

Efficacy (Emax)

Answer 5

the max response produced by the drug, adding more drug wont produce more response because there is 100% occupancy

Question 6

Median effective dose (ED50)

Answer 6

amount of drug that produces a response in 50% of the population

Question 7

Median toxic dose (TD50)

Answer 7

amount of drug that produces a response in 50% of the population

Question 8

Median lethal dose (LD50)

Answer 8

amount of drug that produces a response in 50% of the population

Question 9

6 major neurotransmitters

Answer 9

Serotonin
Norepinephrine
Dopamine
Acetylcholine
Glutamate
GABA

Question 10

5 psychotroptic drug targets

Answer 10

neurotransmitter reuptake
neurotransmitter receptors
neurotransmitter metabolism
Ion channel neurotransmission (2: ligand and voltage gated)

Question 11

Neurotransmitter reuptake

Answer 11

Prevent recycling of NT like serotonin or dopamine by inhibiting reuptake and storage in neuron and inc levels in the synapse and affect post synaptic neurons

Question 12

Neurotransmitter receptors

Answer 12

Many drugs interact with these by binding on the same receptor as the NT or may bind allosterically and change the receptor to enhance or inhibit the NT

Question 13

Neurotransmitter metabolism

Answer 13

Enzymes are another target of drugs as they convert one molecule into another and the enzyme often affect on NT is to break them down

Basically they could inhibit this and allow NT concentrations to circulate

Question 14

Ion channel (2)

Answer 14

Ligand gated which is opened by NT binding

Voltage gated which opened by charge across the membrane

Question 15

reuptake

Answer 15

NT released during neurotransmission are in many cases transported back into the presynaptic neurons and allows reuse and once back in are put in vescicles for storage and protection and ready to redploy

Question 16

presynaptic transporter SERT

Answer 16

for serotonin

Question 17

presynaptic transporter NET

Answer 17

for norepinephrine and dopamine

Question 18

presynaptic transporter DAT

Answer 18

for dopamine

Question 19

presynaptic transporter GABA 1-4

Answer 19

for GABA

Question 20

presynaptic transporter glycine 1-2

Answer 20

for glycine

Question 21

presynaptic transporter: excitatory amino acid transporters 1-5

Answer 21

glutamate
aspartate

Question 22

vesicular transporter VMAT 1-2

Answer 22

serotonin
NE
DA

Question 23

vesicular transporter VAchT

Answer 23

Ach

Question 24

vesicular transporter VIAAT

Answer 24

GABA

Question 25

vesicular transporter V GluT 1-3

Answer 25

glutamate

Question 26

G-protein linked receptors

Answer 26

second messenger system (NT is the first messenger) drug can act at NT binding sites or allosteric sites So NT binds first and changes the receptor allowing the g-protein to bind The G protein makes another change which preps it for the enzyme that synthesizes the second messenger

Question 27

Agonist

Answer 27

When a drug binds to the g protein linked receptor it can affect the receptor in different ways than the endogenous NT Generally produces response similar to the endogenous NT direct: bind to NT receptor at NT site or allosteric site indirect: boost levels of NT by blocking inactivation

Question 28

partial agonist

Answer 28

stabilizers Hard to understand Somewhere on spectrum of agonist that fully activates a receptor and an antagonist that doesn’t change signal transduction Like a light on a dimmer switch

Question 29

antagonist

Answer 29

Usually blocks what an endogenous NT would do to the receptor True antagonists are neutral and because they have no actions of their own they are often called silent Maintain baseline activity

Question 30

partial inverse agonist

Answer 30

inactivates the receptor reduces signal transduction removes baseline activity Opposite extreme of the agonist in that it neither inc signal transduction or blocks agonist activity like an antagonist

Question 31

dopamine receptors and associated class

Answer 31

D1 D2 antipsychotics

Question 32

serotonin receptors and associated class

Answer 32

5HT1A, 2A, 1B/D, 2C, 6, 7 antipsychotics antidepressants anxiolytics

Question 33

norepinephrine receptors and associated class

Answer 33

a-1 a-2 B-2 antidepressant (mirtazapine) antihypertensives antipsychotics

Question 34

Acetylcholine receptors and associated class

Answer 34

M1 M3/M5 antidepressant antihistamines antipsychotics

Question 35

enzymes

Answer 35

convert a substrate into a product Rx can bind to enzyme inhibitors which can be reversible or irreversible Only a few drugs are enzyme inhibitors The ones that bind to inhibitors allow the enzyme to inc interaction with substrate because they inhibit the inhibitor

Question 36

Examples of enzyme targets

Answer 36

In each case the action of the drug prevents the action of the enzyme that degrades the substrate Monoamine Oxidase Acetylcholinesterase Glycogen synthase kinase (GSK) Aldehyde Dehydrogenase

Question 37

Ligand gate is regulated by

Answer 37

receptor gate keeper that hasd the potential to bind an NT or hormone

Question 38

regulation of a ligand gate produces

Answer 38

a confirmation change that opens the channel and allows the flow of charged molecules

Question 39

If agonist occupies a binding site on a ligand gate

Answer 39

the frequency at which the channel opens is increased

Question 40

If antagonist binds to the receptor on a ligand gate

Answer 40

the channel is locked in resting confirmation and similar to if no NT bound

Question 41

If partial agonist binds to ligand gate

Answer 41

will open but less than if full agonist present

Question 42

If inverse agonist binds to ligand gate

Answer 42

channel closes and stabilizes it

Question 43

Allosteric site

Answer 43

It is a site other than which the endogenous ligand binds

Question 44

Allosteric sites have no activity on their own but when bound at the same time as a ligand

Answer 44

they can enhance or block the ligand activity if enhance they are positive and if block they are negative allosteric modulator a. Pos ex is a benzo

Question 45

voltage sensitive

Answer 45

Action potential: Electrical impulse in a neuron Voltage-sensitive sodium channels (VSSCs) Voltage-sensitive calcium channels (VSCCs)