Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology of CNS > Pain, nociception and analgesia > Flashcards

Pain, nociception and analgesia Flashcards

1
Q

What is the definition of Pain?

A

The subjective conscious appreciation of a stimulus that is causing, or threatening to, cause tissue damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the definition of Nociception?

A

The physical process of detection and transmission of a noxious stimuli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are nociceptors?

A

They detect noxious stimuli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the definition of analgesia?

A

Reduction or prevention of either nociception or pain (without loss of consciousness)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do mechanical nociceptors detect?

A 
High intensity mechanical
Strong thermal (>60C)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do polymodal nociceptors detect?

A

High intensity mechanical
Thermal (>45C and <10C)
Chemical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The A(delta) fiber is responsible for what sort of pain?

A

Fast pain
Sharp, pricking
Well-tolerated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The C fiber is responsible for what sort of pain?

A

Slow pain
Burning, aching, throbbing,
Poorly tolerated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which fibers are myolenated? A(delta) or C?

A

A(delta)

This means they transmit signals quicker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which fibers have a larger diameter? A(delta) or C?

A

A(delta)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

ASIC (Acid sensing ion channels) detect what?

A

Acid (H+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

P2X3 (Purinergic receptor) detects what?

A

ATP and Mechanical stimulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

VGNa (Voltage gated sodium ion channel) detects what?

A

Mechanical stimulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

VR-1/TRPV-1 (Vanilloid -1 receptor) detects what?

A

Capsaicin
H+
Heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Is nociception just exaggerated sensory transmission?

A

They conduct at slow velocities
Nociceptors have different thresholds of activation
They have different sites of projection into the spinal cord
They elicit different physiological responses in dorsal horn neurones
Information ascends in different pathways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Nociceptors detect what in relation to heat?

A

Intensity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Thermoreceptors detect what in relation to heat?

A

Presence (not intensity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which neurone(s) synapse to the wide dynamic range neurone?

A

A(delta) fibre only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which neurone(s) synapse to nociceptive neurones

A

Both A(delta) and C fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Spinothalamic pathway

A

Cerebral cortex
Thalamus
Lateral spinothalamic tract
Dorsal root axon (A(d), C)

Responsible for pain, temperature and some touch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Dorsal column - medial lemniscal pathway

A 
Cerebral cortex
Thalamus
Medial lemniscus
Dorsal column
Dorsal root axon (A(a), A(b), A(d)

Responsible for touch, vibration, two point discrimination, proprioception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is referred pain?

A

When two fibres synapse to the same neurone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is hyperalgesia?

A

Increased response to a noxious stimulus

24
Q

What is Allodynia?

A

Painful responses to non-noxious stimulus

25
Q

What is neuropathic pain?

A

Pain unrelated to peripheral nociception, sometimes called pathological pain (serves no purpose)

e.g nerve damage, spinal damage, thalamic stroke

26
Q

What is an itch?

A

Afferent input is via both A(d) and C fibres from free nerve endings.
Inflammation can cause it

However, analgesics don’t inhibit itch!

27
Q

Do analgesics inhibit itch?

A

No

28
Q

What are the differences between A(d) and C fibres PREsynaptically?

A

C fibre terminals contain more substance p (cgrp)

29
Q

What are the differences between A(d) and C fibres POSTsynaptically?

A

Both A(d) and C fibres synapse to AMPA and NMDA receptors

But only C fibres synapse to NK-1 receptors

30
Q

Substance P activates what?

A

Gq GPCR (increased Na/Ca influx, decreased K efflux, increased IP3)

31
Q

TRUE/FALSE? Nociceptor transmission can undergo ‘wind-up’

A

TRUE

32
Q

What chemical inhibits ‘wind-up’

A

2-AP5

33
Q

A(a) and A(b) non-nociceptive mechanoceptors do what in relation to the C-fibre?

A

They inhibit the C-fibre

34
Q

What is supraspinal control of pain?

A

Brain stimulation inhibits nociceptive spinal neurones (causes pain relief)

35
Q

Describe the descending pain pathway

A

Hypothalamus
PAG (Midbrain)
Raphe Nuclei (Medulla)
Dorsal Horn (Spinal Cord)

36
Q

Describe the action of Opioids (in terms of brain regions)

A

Excite/Increase:

  • PAG
  • Nucleus reticulas (medulla) - excites raphe nuclei

Inhibit:

  • Dorsal horn/Spinal cord
  • Periphery
37
Q

What is the action of opioids in the PAG

A

Inhibit both glutamate and GABA release
But glutamate is released from multiple neurones so leads to an overall increase in excitation of the raphe nuclei (medulla).

38
Q

How do opioids inhibit the dorsal horn?

A

Decrease signals from primary afferent neurone and decrease signals coming from PAG + locus coeruleus

Overall decrease in excitation of second order projection neurone

39
Q

What are the endogenous opioid peptides?

A 
B-Endorphin
Enkephalins (Met and Leu)
Dynorphin A(1-17)
40
Q

How do enkephalins work? (in terms of receptors)

A

Activate Gi GPCRs

Leads to decreased Ca influx and increased K efflux
Inhibits production of PKA

41
Q

U-opioid receptors target which site(s) of analgesia?

A

Supraspinal
Spinal
Peripheral

42
Q

K-opioid receptors target which site(s) of analgesia?

A

Spinal

Peripheral

43
Q

Delta-opioid receptors target which site(s) of analgesia?

A

Spinal

44
Q

The descending pain pathway does what?

A

Decreases nociception

45
Q

How do opiates work?

A

Act on opioid receptors

mimic endogenous opioids

46
Q

Opioid receptors activate which type of channel?

A

K (therefore inhibitory)

47
Q

Methadone binds to which opioid receptor(s)

A

U only

48
Q

What are the side effects related to U opioid receptors?

A

Euphoria
Respiratory depression
Constipation

49
Q

What are the side effects related to K opioid receptors?

A

Dysphoria

Diuresis

50
Q

What are the side effects related to delta opioid receptors?

A

Proconvulsant

51
Q

What effects to NSAIDs have?

A

Anti-inflammatory
Anti-pyretic
Analgesic

All effects related to decreased prostaglandin synthesis

52
Q 
Modulation of nociception:
Prostanoid receptor (prostaglandins)
A

Positive effect on BK2 (Bradykinin)

Positive effect on VGNa

53
Q

Modulation of nociception:

BK2 (Bradykinin)

A

Positive effect on VR-1

54
Q

How do NSAIDs work?

A

Inhibit the prostanoid receptors, BK2 and VGNa

Also inhibit COX-1 or COX-2 (which leads to decrease in prostaglandin synthesis)

55
Q

What are the disadvantages of NSAIDs

A

Multiple side effects
Severe gastric irritation
Kidney disorders

Specific COX-2 inhibitors have less side effects

56
Q

COX-1 is found where?

A

Throughout the body (multiple uses, i.e many side effects)

57
Q

COX-2 is involved in what?

A

Just involved in the inflammatory response specifically

Pharmacology of CNS (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions