Synapses and Neurotransmission

Question 1

What neurotransmitter is released from the axon terminal of a neuron when it activates a muscle cell?

Answer 1

ACh

Question 2

What type of ACh receptor does ACh bind to on the postsynaptic side when a neuron stimulates a muscle?

Answer 2

nicotinic

Question 3

What enzyme is responsible for the enzymatic degradation of ACh?

Answer 3

acetylcholinesterase

Question 4

What are 3 pathways for removal of a neurotransmitter from the synaptic cleft?

Answer 4

enzymatic degradation
reuptake
diffusion

Question 5

How is dopamine, NE, and serotonin removed from the synaptic cleft?

Answer 5

reuptake (mono-amine oxidase also enzymatically breaks it down within the terminal)

Question 6

How is glutamate removed from the synaptic cleft?

Answer 6

diffusion- into glial cells

Question 7

What two molecules does acetylcholinesterase break down ACh into?

Answer 7

choline and acetate

Question 8

Where does choline move back to?

Answer 8

presynaptic neuron

Question 9

What two molecules can be reassembled to form acetylcholine

Answer 9

acetyl CoA and choline

Question 10

This disease is an autoimmune disease that causes the immune system to attack nicotinic ACh receptors

Answer 10

Myasthenia gravis

Question 11

How does myasthenia gravis cause weakness?

Answer 11

There is a lack of ACh receptors to receive the ACh

Question 12

How does pyridostigmine improve strength?

Answer 12

inhibits the enzyme that breaks down ACh so it’s left in the synaptic cleft longer

Question 13

_________ serve to bring the membrane closer to threshold for generating an AP

Answer 13

excitatory postsynaptic potential (EPSP)

Question 14

____________ make the cell’s membrane potential more negative, making it harder to generate an AP

Answer 14

inhibitory postsynaptic potential (IPSP)

Question 15

What neurotransmitter classification is ACh?

Answer 15

choline ester

Question 16

What are the 3 catecholamines

Answer 16

dopamine, NE, epinephrine

Question 17

What is the pathway of the 5 molecules involved in catecholamine synthesis

Answer 17

tyrosine–> L-dopa—> dopamine—-> NE—-> epinephrine

Question 18

True or false: there is no dopamine B-hydroxylase in a dopamine neuron

Answer 18

true, that enzyme leads to the production of NE

Question 19

Is there dopamine in an epinephrine cell?

Answer 19

yes, somewhere there has to be since it is a precursor of epinephrine

Question 20

This catecholamine is involved in movement as well as the reward pathway

Answer 20

dopamine

Question 21

This is a movement disorder that involves the loss of dopamine-releasing neurons in the substantia nigra in the basal ganglia

Answer 21

Parkinson’s disease

Question 22

What drug is used to treat Parkinson’s disease?

Answer 22

L-dopa, it passes through BBB

Question 23

Why is L-dopa often given with deprenyl?

Answer 23

deprenyl prevents the breakdown of L-dopa by blocking MAO-B (monoamine oxidase)

Question 24

Is Epi a neurotransmitter or a hormone?

Answer 24

Mainly a hormone, it is released into the blood

Question 25

is NE a neurotransmitter or a hormone?

Answer 25

can act as both

Question 26

What does G protein coupled mean?

Answer 26

if a ligand binds on the outside of the cell, it will have an effect on the inside of the cell

Question 27

What type of receptors are adrenergic receptors?

Answer 27

G protein coupled and linked to second messenger signal pathways

Question 28

This adrenergic receptor is mainly responsible for blood vessels; it causes vasoconstriction and increases BP

Answer 28

A1

Question 29

This adrenergic receptor is responsible for tachycardia, increased myocardial contractility, and increased lipolysis

Answer 29

B1

Question 30

This adrenergic receptor is responsible for bronchodilation

Answer 30

B2

Question 31

This adrenergic receptor presynaptic and is mostly regulatory. It inhibits NE release, ACh release, and insulin release

Answer 31

A2

Question 32

______ __________ are drugs that increase the levels of catecholamins

Answer 32

MAO inhibitors

Question 33

what is serotonin made from?

Answer 33

tryptophan

Question 34

This prevents the reuptake of serotonin into the presynaptic terminal which leaves it in the synapse for a longer period of time

Answer 34

SSRIs (selective serotonin reuptake inhibitors)

Question 35

What are 2 large functions of serotonin?

Answer 35

regulating sleep regulating emotion

Question 36

What is the main excitatory a.a. neurotransmitter?

Answer 36

glutamate

Question 37

What is the main inhibitory a.a. neurotransmitter?

Answer 37

GABA

Question 38

What are the 2 types of glutamate receptors

Answer 38

metabotropic- more complicated ionotropic- ion channels

Question 39

When glutamate binds to _______, it opens a Na+ channel and causes depolarization

Answer 39

AMPA

Question 40

______ acts as a Ca2+ blocker

Answer 40

Mg

Question 41

What type of receptor releases Mg when glutamate binds, which allows Ca2+ to rush in

Answer 41

NMDA

Question 42

What is GABA made from?

Answer 42

glutamate

Question 43

This type of GABA opens a Cl- channel which leads to hyperpolarization

Answer 43

GABAa

Question 44

This type of GABA receptor opens a K+ channel

Answer 44

GABAb (*remember, K+ will move out of the cell)

Question 45

This is released by afferent neurons that relay sensory information into the CNS, especially indicates damage and pain

Answer 45

substance P