Neurochemical Circuitry

Question 1

What are the functions of nitric oxide?

Answer 1

1. retrograde signaling
2. increase cGMP -> regulates Ca homeostasis
3. rapid signaling

Question 2

How is nitric oxide synthesized?

Answer 2

from arginine via NO synthase on demand

Question 3

How is carbon monoxide synthesized?

Answer 3

from heme via heme oxygenase

Question 4

What characteristics do nitric oxide and carbon monoxide share?

Answer 4

• NOT stored in vesicles
• released via diffusion
• NO receptors

Question 5

What are the functions of carbon monoxide?

Answer 5

1. retrograde signaling
2. regulates cGMP -> mediates smooth muscle contraction
3. rapid signaling

Question 6

High affinity receptors are apart of what family?

Answer 6

Trk family

Question 7

Low affinity receptors are apart of what family?

Answer 7

BDNF

Question 8

Where are BDNF and NGF synthesized and released from?

Answer 8

soma and dendrites

Question 9

Where are BDNF and NGF synthesized and released from after depolarization?

Answer 9

soma, dendrites, nerve terminals

Question 10

What are the effects of BDNF?

Answer 10

• neurogenesis
• excitability
• brain connectivity

Question 11

What is the effect of too much BDNF?

Answer 11

affects plasticity and may affect learning

Question 12

What is the effect of too little BDNF?

Answer 12

affects plasticity and linked to increased depressive episode

Question 13

How is Ach synthesized?

Answer 13

choline + acetyl CoA by enzyme choline acetyltransferase

Question 14

How is the action terminated in Ach?

Answer 14

hydrolysis by ACHE

Question 15

What is the effect of too much ACh?

Answer 15

muscle contractions (ex: black widow venom)

Question 16

What is the effect of too little ACh?

Answer 16

paralysis

Question 17

What are the cholinergic circuits?

Answer 17

1. basal forebrain neurons: degenerate in Alzheimer’s
2. brainstem neurons: induces REM

Question 18

How is serotonin synthesized?

Answer 18

from tryptophan by enzyme tryptophan hydroxylase

Question 19

How is the action temrinated in serotonin?

Answer 19

1. reuptake into presynaptic terminal
2. catabolized by MAO-A

Question 20

What are the indicated effects of serotonin?

Answer 20

• mood control
• homeostasis
• appetite & digestion

Question 21

What is the effect of too much serotonin?

Answer 21

serotonin syndrome:
* confusion
* twitching/trembling
* dialted pupils
* shivering/goosebumps
* headache
* sweating/diarrhea
* irregular/fast heart beat

Question 22

What is the effect of too little serotonin?

Answer 22

schizophrenia: depression, sleep changes

Question 23

What are serotonergic circuits?

Answer 23

1. caudal raphe nucleus
2. rostral raphe nucleus

Question 24

How is dopamine synthesized?

Answer 24

from tyrosine by enzyme tyrosine hydroxylase

Question 25

How is the action terminated in dopamine?

Answer 25

1. reuptake into pre-post synaptic terminal

Question 26

What are the indicated effects?

Answer 26

1. modulating movement 2. inhibition of unwanted movement

Question 27

What are the effects of too much dopamine?

Answer 27

schizophrenia

Question 28

What are the effects of too little?

Answer 28

parkinson's disease

Question 29

What are the dopaminergic circuits?

Answer 29

1. ventral tegmental area 2. substantia nigra

Question 30

What is the ventral tegmental area?

Answer 30

* important for goal oriented/reward behaviors * actviated by drugs of abuse

Question 31

What is substantia nigra?

Answer 31

* degenerate Parkinson's disease * control posture and movement

Question 32

What is the key factor in liking?

Answer 32

serotonin -> mood stabilizer, wellbeing, happiness

Question 33

What is the key factor in wanting?

Answer 33

dopamine -> motivational role in brain's reward system

Question 34

What is norepinephrine synthesized by?

Answer 34

dopamine -> tyrosine by enzyme tyrosine hydroxylase

Question 35

How is dopamine transported into vesicle ?

Answer 35

VMAT2

Question 36

How does dopamine turn into norepinephrine?

Answer 36

beta-hydroxylation

Question 37

How is action terminated in norepinephrine?

Answer 37

1. reuptake into pre-synaptic terminal 2. catabolized by MAO-A and COMT

Question 38

What are the indicated effects of norepinephrine?

Answer 38

alertness/attention

Question 39

What is the effect of too much norepinephrine?

Answer 39

icnreased blood pressure, anxiety, sweating, headaches

Question 40

What is the effct of too little norepinephrine?

Answer 40

lethargy, lock of focus, depression

Question 41

What is the noradrenergic circuit?

Answer 41

locus coeruleus

Question 42

How is glutamate synthesized?

Answer 42

from glutamine by enzyme glutaminase

Question 43

How is glutamate transported into the vesicle?

Answer 43

VGLUT

Question 44

How is the action temrinated in glutamate?

Answer 44

excitatory amino acid transproter

Question 45

Which 2 circuits are widespread?

Answer 45

glutaminergic and GABA

Question 46

What are the indicated effects of glutamate?

Answer 46

1. main excitatory neurotransmitter 2. role in synaptic plasticity, learning, and memory 3. role in seizures

Question 47

What is the effect of too much glutamate?

Answer 47

excitotoxicity and seizures

Question 48

What is the effect of too little glutamate?

Answer 48

psychosis, coma, and death

Question 49

How is GABA synthesized?

Answer 49

dopamine -> glutamate by enzyme glutamic acid decarboxylase

Question 50

How is the action terminated in GABA?

Answer 50

GABA transporter

Question 51

What is the indicated effects of GABA?

Answer 51

main inhibitory neurotransmitter

Question 52

What is the effect of too much GABA?

Answer 52

over-sedation, over-relaxing of muscle including the heart and respiration

Question 53

What is the effect of too little GABA?

Answer 53

anxiety, seizures

Question 54

What is an agonist of GABA receptors?

Answer 54

baclofen

Question 55

What is an antagonist of glutamate?

Answer 55

ketamine