Pain and Nociception

Question 1

What is the difference between Pain and Nociception

Answer 1

Pain = Subjective response
Nociception = Physiological response

Question 2

Some types of pain serve no useful purpose. Give such examples of pain

Answer 2

Chronic pain
Rheumatic pain
Cancer pain
Neuropathic pain
Amputation pain

Question 3

How can you characterise pain based on origin

Answer 3

Somatic pain (Superficial + Deep)
Visceral pain

Question 4

Visceral pain affects where in the body?

Answer 4

Organs of the thorax and abdominal cavity

Question 5

How can you characterise pain based on duration

Answer 5

Acute (normal pain)

Chronic pain

Question 6

Chronic pain has what kind of duration?

Answer 6

> 3 months

Question 7

What receptors detect pain, and along what neurone to they travel to get to the CNS

Answer 7

Nociceptors
Travel along the primary afferent fibre through the Dorsal Route Ganglion into the spinal cord, specifically the dorsal horn

Question 8

Noiceptors are sensors found on most body tissues, and consist of…?

Answer 8

Unspecialised nerve cell endings or “free nerve endings”

Question 9

What are the five different types of nociceptors

Answer 9

Thermal
Mechanical
Chemical
Polymodal
Sleeping / Silent

Question 10

Polymodal receptors are a combination of what 3 Nociceptors

Answer 10

Thermal
Mechanical
Chemical

Question 11

What are the four types of Primary afferent fibres

Answer 11

Aa
Ab
Ad
C

Question 12

Low threshold mechanoreceptors have what class of Primary Afferent Fibre?

Answer 12

Aa and Ab

Question 13

Which primary afferent fibres are slow conducting and small diameter?

Answer 13

Ad and C

Question 14

Polymodal nociceptors have which fibres?

Answer 14

C

Question 15

First and second pain is characterised by which fibres?

Answer 15

Ad and C

Question 16

First pain is described as what?

Answer 16

Sharp / prickling

Question 17

Are C fibres myelinated or unmyelinated?

Answer 17

Unmyelinated

Question 18

Second pain is described as what?

Answer 18

Dull, aching and burning

Question 19

How is congenital analgesia caused?

Answer 19

Mutation in genes encoding Na+ channels

Question 20

What is congenital analgesia?

Answer 20

They have an inability to feel pain

Question 21

C fibres terminate in which Lamina?

Answer 21

Lamina II

Question 22

Ad fibres terminate in which Lamina?

Answer 22

Lamina I

Question 23

Nociceptive Pathway follows which tract?

Answer 23

The spinothalamic tract

Question 24

The spinothalamic tract / nociceptive pathway decussates and is relayed via _________ to the _______ to the ________?

Answer 24

Via medulla to thalamus to somatosensory cortex

Question 25

The main neurotransmitters involved in Nociception are what?

Answer 25

Glutamate and Substance P

Question 26

How is referred pain caused?

Answer 26

Caused by convergence of nociceptor inputs from the viscera and skin

Question 27

What does the Gate theory explain?

Answer 27

Why pain is reduced by stimulating mechanoreceptors, i.e. rubbing your knee after falling over

Question 28

What is allodynia?

Answer 28

Touch-evoked pain when it normally shouldn’t

Question 29

What is hyperalgesia?

Answer 29

Increased pain sensation from something which usually causes only a little pain

Question 30

What is primary and secondary hyperalgesia?

Answer 30

Primary = occurs in the site of tissue damage

Secondary = occurs around the site of tissue damage

Question 31

Give four examples of pharmacological interventions used to treat pain

Answer 31

Opiods
NSAIDs
Local anaesthetics
Psychotropic drugs

Question 32

What is a rhizotomy?

Answer 32

Cutting of dorsal roots, is a surgical intervention

Question 33

Give examples of three endogenous opiods

Answer 33

Endorphins
Enkephalins
Dynorphins

Question 34

What are the three types of opiod receptors?

Answer 34

Mu
Delta
Kappa

Question 35

What is Naloxone?

Answer 35

An opiod selective receptor antagonist. Used to reverse opiod induced respratory depression and opiod overdose