Week 3

Question 1

What changes lead to maladaptive of physiological processes which is root of disease?

Answer 1

Non-genomic
Genomic
Epigenetic

Question 2

What is sensing?

Answer 2

Fundamental process that can be found from single cell organisms to complicated organisms

Question 3

What has the same sensing and processes been adapted and evolved to give?

Answer 3

Complicated physiological processes within bodies e.g. regulation of blood pressure

Question 4

What are examples of simple sensing?

Answer 4

Avoidance or attraction in single cell organism to noxious or desirable stimuli
Withdrawal reflexes to noxious stimulus in animals

Question 5

What is examples of complex sensing?

Answer 5

Homeostatic mechanism e.g. blood pressure regulation

Behaviours e.g. communication and complex motor behaviours

Question 6

Classical

Answer 6

Sound, hearing

Question 7

Non-classical

Answer 7

Proprioception

Touch

Question 8

Reflex arc

Answer 8

Forms part of the afferent pathway which sends input into the brain

Question 9

When does the first nerve fibre respond?

Answer 9

Once pain is reached

Nociceptor - responsible for mediating pain

Question 10

Second nerve fibre

Answer 10

Responds lower but continues to increase its firing in its noxious range

Question 11

Third nerve fibre

Answer 11

Low threshold unit
Involved in physiological functions
Give mediators like capsaicin

Question 12

What expresses ASIC1a ion channel?

Answer 12

ASIC sensitive current evoked in a cell

Question 13

What is sensory processing?

Answer 13

Taking external signal and transforming it into AP which will be taken to the brain and interpreted in a meaningful way

Question 14

What does voltage threshold trigger?

Answer 14

All or nothing action potential

Question 15

What cannot be recorded?

Answer 15

Very thin nerve endings

Question 16

What is the process of stimulus-transduction in sensory nerves about?

Answer 16

Moving the resting membrane potential

Question 17

What is the purpose of TTX?

Answer 17

Differentiate Na+ current into fast and slow TTX resistant, sensitivity component

Question 18

What is ASICS?

Answer 18

Sensitive to acid 
More permeable to sodium than calcium 
2 transmembrane domains 
Homomeric and heteromeric complex 
Big extracellular domain

Question 19

What is the function of ASICS?

Answer 19

Drive sodium into nerve endings to trigger generator potential

Question 20

TRPV1

Answer 20

Acid
Capsaicin
Anandamide

Question 21

TRPV2

Answer 21

Cannabidiol

THC

Question 22

TRPV3

Answer 22

Camphor
Menthol
Clove

Question 23

TRPV4

Answer 23

Anandamide

Arachidonic acid

Question 24

TRPA1

Answer 24

Mustard
Cinnamon
formaldehyde

Question 25

TRPM8

Answer 25

Menthol Peppermint eucalyptus

Question 26

Mechanical: TRP | What is ruthenium red?

Answer 26

Broad spectrum TRP channel blocker

Question 27

What was the experiment done on mechanical TRP?

Answer 27

Probed the bowel Recorded activity in the sensory nerve Presence of TRP channel blocker - reduction in the afferent response

Question 28

What is TRP channel responsible for?

Answer 28

Mechanotransduction that occurs in the bowel

Question 29

What happens when you apply a mechanical stimulus in TRPA1 in wild type mouse?

Answer 29

Robust response

Question 30

What does TRP channel transduce?

Answer 30

Mechanical stimuli by moving ca2+ into nerve endings

Question 31

ASICS

Answer 31

H+ gated Na+ channel which are present in most, if not all, neurons elicited by a rapid drop in extracellular PH Good sensors for detecting protons

Question 32

What is ASIC3?

Answer 32

Generates biphasic current | Fast inactivating and a slow sustained phase

Question 33

ASIC3

Answer 33

Increased cutaneous AB fibre response | Decreased visceral afferent response

Question 34

ASIC 2

Answer 34

Increased sensitivity visceral afferents | Reduced cutaneous AB fibre response

Question 35

ASIC 1

Answer 35

Increased sensitivity visceral afferent | No effect cutaneous afferent

Question 36

What is TREK/TRAAK K channels responsible for?

Answer 36

Background “leak” potassium conductance

Question 37

What are mechanical (TREK/TRAAK) channels holding?

Answer 37

The resting membrane potential | Allow us to sensitise the system

Question 38

What do we have the capacity to directly influence?

Answer 38

Nerve endings through transducer channels

Question 39

Descend the bowel

Answer 39

Pressure increases More ATP released Inhibit afferent response

Question 40

What does secondary transducer cell release ?

Answer 40

Mediators that diffuse to stimulate nerve endings