CNS

Question 1

What amino acid are dopamine, norepinephrine, and epinephrine derived from?

Answer 1

Tyrosine (Tyr, Y)

Question 2

What are three possible pathways that dopamine, norepi, and epi can take in the post-synaptic cleft?

Answer 2

1. re-uptake into the neuron and metabolized
2. bind to post-synaptic receptor
3. bind to autosynaptic receptor to inhibit signal

Question 3

What amino acid is serotonin derived from?

Answer 3

Tryptophan (Trp, W)

Question 4

What is another name for serotonin?

Answer 4

5-hydroxytryptamine (5HT)

Question 5

What converts dopamine to norepinephrine?

Answer 5

dopamine-beta-hydroxylase

Question 6

What converts norepinephrine to epinephrine?

Answer 6

phenylethanolamine N-methyltransferase (PNMT)

Question 7

What is direct action of a neurotransmitter?

Answer 7

the neurotrasmitter binds to and opens ion channels - elicits rapid response

Question 8

What is indirect action of a neurotransmitter?

Answer 8

the neurotransmitter acts through intracellular secondary messengers (usually G-proteins) to open ion channels - longer and broader response

Question 9

What is the difference between voltage-gated and ligand-gated membrane channels?

Answer 9

voltage-gated open/close in response to voltage changes across the membrane (potential) :: ligand-gated open/close in response to a molecule binding to the channel

Question 10

Difference between ionotropic and metabotropic receptors?

Answer 10

Ionotropic = direct ligand binding to open channel
Metabotropic = indirect/secondary messenger signal to open channel

Question 11

What are the two types of metabotropic receptors?

Answer 11

Membrane-delimited: all secondary messenger molecules are entirely in plane of membrane (think attached to membrane)
Diffusible second messengers: messenger molecules travel through cytoplasm to get to target

Question 12

What are autoreceptors?

Answer 12

Receptors on an axon terminal that the axon’s own transmitter can bind to elicit a response on that axon (usually inhibitory)

Question 13

What are heteroreceptors?

Answer 13

Receptors on an axon terminal that recieves transmitters from other axons

Question 14

What are the three catecholamines?

Answer 14

dopamine, norepinephrine, and epinephrine

Question 15

What are two amino acid transporters?

Answer 15

GABA & Glutamate

Question 16

What is acetylcholine derived from?

Answer 16

Choline brought into the neuron by choline transporter

Question 17

Why must ACh be made from choline?

Answer 17

Because there is NO transporter that will transport ACh across a membrane, so choline is brough into cell to make ACh

Question 18

What kind of receptor can ACh bind?

Answer 18

nicotinic or muscarinic

Question 19

What metabolizes ACh into choline on the post-synaptic cell?

Answer 19

Acetylcholinesterase

Question 20

What benefit does an astrocyte provide for Glutamate levels?

Answer 20

Astrocytes help metabolize and regulate Glu levels

Question 21

What is Glu derived from in neuron?

Answer 21

alpha-Ketoglutarate

Question 22

What three receptors can Glu bind post-synaptically?

Answer 22

Kainate, NMDA, or AMPA

Question 23

What does an astrocyte do with Glu?

Answer 23

Metabolize it into Glutamine (Gln)

Question 24

What is GABA derived from?

Answer 24

Glutamate (Glu)

Question 25

What is GABA made into inside the astrocyte?

Answer 25

succinate

Question 26

What enzyme converts Glu to GABA?

Answer 26

Glutamate decarboxylase

Question 27

What kind of post-synapse receptors does GABA bind?

Answer 27

Either GABA-alpha or GABA-beta

Question 28

What do mu-receptors do to GABA concentration?

Answer 28

They inhibit GABA production and release

Question 29

What is an endorphin?

Answer 29

A mu-receptor ligan that can inhibit GABA release