Autonomic Nervous System

Question 1

What NT is used in parasympathetic preganglionic nerve terminals?

Answer 1

ACh (n)

Question 2

What NT is used in parasympathetic postganglionic nerve terminals?

Answer 2

ACh (m)

Question 3

What NT is used in sympathetic preganglionic nerve terminals?

Answer 3

ACh (n)

Question 4

What NT is used in sympathetic post ganglionic nerve terminals?

Answer 4

NA

Question 5

What NT is used in sympathetic post ganglionic sweat gland nerve terminals?

Answer 5

ACh (m)

Question 6

Give 3 examples of organs where parasympathetic innervation and activity increases secretion.

Answer 6

Salivary glands
GI tract glands
Bronchi glands

Question 7

Give two examples of organs where parasympathetic innervation and activity increases muscle contraction.

Answer 7

Bladder

Eye ciliary muscle

Question 8

Give two examples of organs where sympathetic innervation and activity increases muscle contraction.

Answer 8

Heart

Uterus

Question 9

Which component of the ANS mediates a slowing of the heart and decreased force of contraction?

Answer 9

The parasympathetic:

The vagus nerve which extends from the medulla

Question 10

How is ACh produced?

Answer 10

Produced in the nerve cytosol by CAT from choline and acetate

Question 11

How is ACh packaged?

Answer 11

Takes from the cytosol into vesicles by an ACh carrier on the vesicle

Question 12

How is ACh released?

Answer 12

Calcium-dependent exocytosis

Question 13

How is ACh inactivated?

Answer 13

Inactivated by AchE in the synapse

Choline is takes up into the presynaptic neurone

Question 14

Where in the somatic nervous system are ACh-gated ion channels found?

Answer 14

Neuromuscular junction

Question 15

Where in the ANS are ACh-gated ion channels found?

Answer 15

Ganglionic synapses

Question 16

Describe a drug which antagonises ACh-gated ion channels.

Answer 16

Tubocurarine:
Antagonises post ganglionic nAChRs
Used as an adjunct to anaesthesia
Muscle relaxant

Question 17

Describe a drug which prevents the exocytosis of ACh vesicles.

Answer 17

Butolinum:
Inhibits activity of ACh- gated ion channels
Used for Botox
Used for spasms and dystonia

Question 18

Name a drug which inhibits heart mAChRs.

Answer 18

Atropine:

Increases heart rate

Question 19

Name a drug which inhibits eye muscle mAChRs.

Answer 19

Tropacamide:

Induces mydriasis and ciliary muscle paralysis for eye retina exam

Question 20

Name a drug that inhibits mAChRs in lung smooth muscle.

Answer 20

Ipratropium:

Relieves muscle spasm in acute asthma

Question 21

Name a drug that inhibits mAChRs for the stomach and secretion.

Answer 21

Atropine:

Secretions are reduced

Question 22

Name a drug that inhibits mAChRs for the brain.

Answer 22

Atropine:

Anti emetic

Question 23

Why isn’t ACh used therapeutically?

Answer 23

It’s broken down by AChE too quickly

Question 24

Give an example of a cholinergic agonist.

Answer 24

Carbachol:

Resistant to AChE so lasts much longer

Question 25

What enzyme breaks down ACh? Where is it found?

Answer 25

AChE | found in the synapse

Question 26

What is a short lasting AChE blocker and what is it used for?

Answer 26

Edrophonium: | Diagnosis of myasthenia gravis

Question 27

What is a medium lasting AChE blocker and what is it used for?

Answer 27

Erosine: | Quicker recover from competitive curare

Question 28

What is a long lasting AChE blocker and what is it used for?

Answer 28

Organophosphates: Insecticides Nerve gas

Question 29

How is NA produced?

Answer 29

L-tyrosine is ingested L-tyrosine is converted to L-DOPA by tyrosine hydroxylase L-DOPA is converted to dopamine by DOPA decarboxylase Dopamine is converted to NA by dopamine beta-hydroxylase

Question 30

How is NA packaged?

Answer 30

Dopamine is taken into vesicles, it is then converted to NA

Question 31

How is NA released?

Answer 31

Calcium dependent exocytosis

Question 32

How is NA deactivated?

Answer 32

Taken up into presynaptic terminal or metabolised by COMT

Question 33

What receptors may be present at an adrenergic synapse?

Answer 33

Presynaptic alpha(2) autoreceptor Presynaptic beta (2) adrenoreceptor Post synaptic beta (2) adrenoreceptor Post synaptic ATP receptors

Question 34

List the adrenaline/ NA gated ion channels

Answer 34

There are none

Question 35

List the adrenaline/ NA GPCRs

Answer 35

``` Beta 1- Gs (+) Beta 2- Gs (+) Beta 3- Gs (+) Alpha 1- Gq (+) Alpha 2- Gi (-) ```

Question 36

Where is NA produced and released?

Answer 36

Produced in the adrenal medulla | Released from presynaptic neurones

Question 37

Where is adrenaline produced and released from?

Answer 37

Produced in the adrenal medulla | Released from the adrenal medulla

Question 38

Where is isoprenaline produced and released from?

Answer 38

It's a synthetic catecholamine.

Question 39

What second messenger system does alpha 1 affect?

Answer 39

Activates PLC | Increases DAG and IP(3)

Question 40

What second messenger system does the alpha 2 receptor affect?

Answer 40

Inactivates AC | Decreases cAMP

Question 41

What second messenger systems do the beta receptors affect?

Answer 41

Activates AC | Increases cAMP

Question 42

Describe a therapeutic antagonist for alpha 1.

Answer 42

Doxazosin: Treats hypertension Treats benign prostatic hypoplasia

Question 43

Describe a therapeutic alpha 2 antagonist

Answer 43

Mirtazapine: | Treats depression

Question 44

Describe a therapeutic beta receptor antagonist.

Answer 44

Propranolol: | Treats hypertension and tachycardia

Question 45

How may the synaptic concentration of NA be increased without increasing the amount of NA

Answer 45

Presynaptic alpha 2 antagonist NET antagonist Uptake 2 inhibitor MOA inhibitor