The Biogenic Amines

Question 1

Name the 5 Biogenic amine neurotransmitters

Answer 1

3 Catecholamines: Dopamine, Norepinephrine, and Epinephrine

Histamine
Serotonin

Question 2

Catecholamines are derived from this common precursor:

Answer 2

The amino acid Tyrosine

Question 3

The first step in synthesizing a catecholamine is to:

Answer 3

Synthesize dihydroxyphenylalanine (DOPA)

Question 4

What is required to synthesize DOPA?

Answer 4

Needs a reaction of Tyrosine hydroxylase, Oxygen (substrate), and tetrahydrobiopterin (co-substrate)

Question 5

Dopamine is produced by what action?

Answer 5

The action of DOPA decarboxylase on DOPA

Question 6

Major Dopamine containing area of the brain

Answer 6

Corpus Striatum

Question 7

What is the Corpus Striatum?

Answer 7

a collective name given to the caudate nucleus and lentiform nucleus within the basal ganglia.

Question 8

The Corpus Striatum receives input from

Answer 8

All over the cortex and importantly the substantia nigra at the base of the midbrain

Question 9

Corpus Striatum play an essential role in what?

Answer 9

coordination of body movements.

Question 10

What’s up with Parkinson’s and Dopamine?

Answer 10

Dopaminergic neurons of the substantia nigra degenerate leading to motor dysfunction

Question 11

Besides motor movements what else does Dopamine play a role in?

Answer 11

motivation, reward, and reinforcement.

Question 12

What’s up with Cocaine and Dopamine?

Answer 12

Cocaine acts by stimulating the release of Dopamine

Question 13

Dopamine binds to…

Answer 13

Dopamine receptors and certain β-adrenergic receptors

Question 14

What’s up with Dopamine and the treatment of Shock?

Answer 14

It’s used clinically to treat shock because it dilates renal arteries through dopamine receptor activation and increases cardiac output by activating β-adrenergic receptors in the heart

Question 15

The synthesis of Norepinephrine requires

Answer 15

dopamine β-hydroxylase and the transport of dopamine into adrenergic terminals via vesicles

Question 16

The most prominent class of neurons that synthesize norepinephrine is

Answer 16

sympathetic ganglion cells

Question 17

Norepinephrine is also highly utilized by this brain region

Answer 17

Locus Coerulus

Question 18

Norepinephrine in the Locus Coerulus influences:

Answer 18

sleep & wakefulness
Attention
Feeding Behavior

Question 19

Among the Catecholamines, this one is present at lower levels

Answer 19

epinephrine

Question 20

Enzyme that synthesizes epinephrine

Answer 20

phenylethanolamine-N-methyltransferase

Question 21

Phenylethanolamine-N-methyltransferase is found only in

Answer 21

epinephrine-secreting neurons

Question 22

Epinephrine containing neurons in the CNS are found in two groups in this brain region:

Answer 22

rostral medulla

Question 23

What is the function of epinephrine in the rostral medulla

Answer 23

This is not known

Question 24

What happens after to catecholamines left in the synaptic gap?

Answer 24

They are removed by reuptake into nerve terminals or surrounding glial cells by a Na+ dependent transporter.

Question 25

Two major enzymes involved in catabolism of catecholamines are:

Answer 25

``` Monoamine Oxidase (MAO) and Catechol O-methyltransferase (COMT) ```

Question 26

Histamine is produced from this amino acid

Answer 26

Histidine

Question 27

Histamine is metabolized by

Answer 27

Histamine methyltransferase AND MAO combined actions

Question 28

High concentrations of histamine are found in

Answer 28

the hypothalamus

Question 29

What does the central histamine projections mediate?

Answer 29

arousal and attention

Question 30

When is Histamine released from Mast cells?

Answer 30

In response to allergic reactions or tissue damage

Question 31

Chemical name of Serotonin

Answer 31

5-hydroxytryptamine (5-HT)

Question 32

5-HT is synthesized from this amino acid

Answer 32

tryptophan

Question 33

How is tryptophan hydroxylated? By what enzyme?

Answer 33

Tryptophan is taken into the neuron by a plasma membrane transporter. The enzyme that catalyzes the reaction is tryptophan 5-hydroxylase

Question 34

Where is Serotonin located?

Answer 34

in neurons of the raphe region of the pons and upper brainstem (with wide projections into the forebrain)

Question 35

What has Serotonin been implicated in the regulation of?

Answer 35

Sleep and wakefullness