Mod 3 - Site of Drug Action

Question 1

two categories of drugs that affect synaptic transmission

Answer 1

antagonists and agonists

Question 2

drugs that block or inhibit the postsynaptic effects

Answer 2

antagonists

Question 3

drugs that facilitate postsynaptic effects

Answer 3

agonists

Question 4

how do some psychoactive drugs produce their affects?

Answer 4

by altering the production of neurotransmitters

Question 5

most neurotransmitters are produced from -

Answer 5

precursors

Question 6

how do some drugs act as precursors

Answer 6

increase the amount of neurotransmitter a cell can synthesize and release into the synapse

Question 7

precursor drugs are considered -, because administering them increases activity of the neurotransmitter system

Answer 7

agonists

Question 8

a precursor for dopamine; involved in Parkinson’s disease treatment

Answer 8

L-DOPA

Question 9

neurotransmitter synthesis is controlled by -

Answer 9

enzymes

Question 10

how does a drug affect enzymes?

Answer 10

if a drug deactivates one of the enzymes that synthesize neurotransmitters, it will prevent the neurotransmitter from being produced; decreases amount of neurotransmitter

Question 11

drugs that deactivate enzymes are -

Answer 11

antagonists

Question 12

• inhibits an enzyme necessary for the synthesis of serotonin

Answer 12

p-chlorophenylalanine (PCPA)

Question 13

• pump molecules of the neurotransmitter across the vesicle membrane, filling the vesicles

Answer 13

vesicle transporters

Question 14

true or false. the vesicle transporters are not different from the transporters found on the terminal membrane

Answer 14

false. it is different

Question 15

how are terminal membrane transporters and vesicle transporters different?

Answer 15

terminal membrane transporters move the molecules form the synapse into the cytoplasm of the presynaptic cell; the vesicle transporters then move the molecules into the vesicles

Question 16

how do drugs act as antagonists in terms of vesicle transporters

Answer 16

they block them, binding with a particular site on the transporter and inactivating it; because the synaptic vesicles remain empty, nothing is released when the vesicles eventually release their contents into the synapse

Question 17

ex. of a drug that blocks vesicle transporters for monoamine neurotransmitter systems; sometimes used to reduce blood pressure

Answer 17

reserpine

Question 18

how do drugs act as antagonists in terms of the proteins at terminal buttons?

Answer 18

by preventing the release of neurotransmitters from the terminal button; deactivate the proteins that cause docked synaptic vesicles to fuse with the presynaptic membrane and expel their contents into the synaptic cleft

Question 19

ex. of drugs that act as antagonists at the terminal button; prevents the release of acetylcholine

Answer 19

botulinum toxin (botox)

Question 20

effects on receptors depend on -

Answer 20

1. where the receptor is located
2. what its normal effects are
3. whether the drug activates the receptor or blocks its actions

Question 21

a drug that mimics the effects of a neurotransmitter act as -

Answer 21

direct agonists

Question 22

drugs that bind with receptors and block their activation act as -

Answer 22

direct antagonists/receptor blockers

Question 23

how do drugs act as direct antagonists/receptor blockers?

Answer 23

they occupy the the receptor’s binding site, preventing the neurotransmitter from activating the receptor

Question 24

some receptors have multiple binding sites… binding of a molecule with an alternative site is referred to as -

Answer 24

noncompetitive binding

Question 25

if a drug attaches to an alternative site and prevents the ion channel from opening, it’s called a -

Answer 25

indirect antagonist

Question 26

if a drug attaches to an alternative site and facilitates the opening of the ion channel, it is called a -

Answer 26

indirect agonist

Question 27

drugs that selectively activate presynaptic receptors act as -

Answer 27

antagonists

Question 28

drugs that bock presynaptic autoreceptors, increasing the release of the neurotransmitters, act as -

Answer 28

agonists

Question 29

how do drugs affect reuptake?

Answer 29

some drug molecules attach to the terminal membrane transporter molecules responsible for reuptake and inactivate them; blocking reuptake

Question 30

how do drugs affect deactivation of enzymes?

Answer 30

bind the with the enzymes that normally destroy the neurotransmitter and prevent them from working

Question 31

drugs that affect either reuptake and enzymatic deactivation are -

Answer 31

agonists, because they both prolong the presence of molecules of the neurotransmitter in the synaptic cleft

Question 32

effects of drugs on storage of neurotransmitters in the synaptic vesicles? (antagonist)

Answer 32

block vesicle transporters, decreasing neurotransmitters available

Question 33

how do drugs affect the release of neurotransmitters through vesicles (antagonist)

Answer 33

bind to and deactivate the proteins that allow the fusion of vesicles to the membrane

Question 34

when drugs mimic neurotransmitters, they act as

Answer 34

direct agonists

Question 35

when drugs bind to the same site at neurotransmitter and blocks the receptor from being activated, it acts as

Answer 35

a direct antagonist

Question 36

when drugs bind to different site on receptor than neurotransmitter and prevent ion channels from opening, they act as

Answer 36

indirect antagonist

Question 37

when drugs bind to different site on receptor than neurotransmitter and causes ion channels to open, they act as

Answer 37

indirect agonist

Question 38

drugs that activate autoreceptors are

Answer 38

antagonists; because they stimulate the decrease of neurotransmitters released

Question 39

drugs that block autoreceptors are

Answer 39

agonists; because they block the regulation of neurotransmitters produced, producing more