Brainscape's Knowledge GenomeTM

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


See full index

PHTH 7303 Neuro > Exam 3 Week 13 ppt 6 Pain peripheral and central component > Flashcards

Exam 3 Week 13 ppt 6 Pain peripheral and central component Flashcards

1
Q

Nociceptors are

A

unencapsulated endings that are categorized by the environmental stimulus

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

Nociceptors responds to

A

mechanical, thermal, chemical or all of these (polymodal)

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

Mechanical nociceptors- respond to

A

respond to intense mechanical stimuli

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

Mechanical nociceptors- fibers

A

have small myelinated (Ad) afferent axons

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

Thermal nociceptors- respond to

A

Respond to intense cold (below 5°C) or intense heat (above 45 C)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Thermal nociceptors- fibers

A

have myelinated (Ad) or unmyelinated (C ) afferent axons

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

Chemical nociceptors- respond to (3)

A

Respond to ions (K+ and H+), local inflammation mediators (histamine) and other chemicals (capsaicin)

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

Polymodal nociceptors- respond to

A

Respond to mechanical, thermal or chemical stimuli

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

Polymodal nociceptors- fibers

A

Small unmyelinated (C) afferent axons

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

two calibers of nociceptive afferent fibers there lead to a theory called

A

phenomenon of Double pain

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

phenomenon of Double pain (created by)

A

~First described by Lewis and Pochin (1937) where all the illustrations were labeled with their initials because they studied it by dropping hot metal on each other

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

phenomenon of Double pain (details)

A

~Sharp, stabbing pain followed by burning and aching sensation
—-Fast (1st) pain – Ad fiber 1° afferent – small myelinated
—-Slow (2nd) pain – C fiber 1° afferent - small unmyelinated
~More of theoretical than practical value

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

phenomenon of Double pain (details on fast pain)

A

~sharp stabbing pain or Fast (1st) pain arises from Ad fiber 1° afferent, small myelinated fibers

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

phenomenon of Double pain (details on slow pain)

A

~achy burning pain or Slow (2nd) pain arises from the C fiber 1° afferent, the unmyelinated fibers

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

3 different abnormal responses to stimulation of nociceptors

A

~peripheral sensitization
~hyperalgesia
~allodynia

(I’m pretty sure that hyeralgesia and allodynia are types of peripheral sensitization)

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

Peripheral sensitization (general/ what is it)

A

~enhance responsiveness of nociceptors
~Increased sensitivity of nociceptors and primary afferents to noxious stimuli or a responsiveness of these receptors to non-noxious stimuli such as touch

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

Hyperalgesia

A

Exaggerated sensitivity to noxious stimuli

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

Allodynia

A

Normally innocuous stimuli evokes the perception of pain

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

Peripheral sensitization can be produced by

A

~Local release of sensitization agents from mast cells

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

examples of sensitization agents form mast cells (in peripheral sensitization)

A

~Prostaglandins
~Bradykinin
~Histamine
~Serotonin (5-HT)

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

in peripheral sensitization, local release of sensitizing agents may produce

A

Axon reflexes where Antidromic impulses from 1° afferent will cause the release of substance P at distal ending producing inflammation

[An antidromic impulse in an axon refers to conduction opposite of the normal (orthodromic) direction[citation needed]. That is, it refers to conduction along the axon away from the axon terminal(s) and towards the soma.
(wikipedia)]

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

Variety of nerve problems result in

A

pain

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

most severe form of nerve pain is

A

ectopic pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Ectopic pain is

A

~activity along nociceptive afferents from site of damage not nerve terminal.
~results from a denuded axon
~can lead to an accumulation of Na+ channels in denuded area
~gives rise to an excitable area of axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

ectopic pain (signs)

A

~positive Tinel’s sign over an unusual area of nerve

~only light tapping over an area of inflammation can produce severe pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

CRPS stands for

A

Complex Regional Pain Syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Complex Regional Pain Syndrome is

A

~severe chronic musculoskeletal pain syndrome

~commonly seen in the extremities where non-nociceptive stimulation causes pain

28
Q

Complex Regional Pain Syndrome: 2 forms

A

Type 1

Type 2

29
Q

Complex Regional Pain Syndrome- type 1

A

~not associated with demonstrable nerve lesions

~formerly called reflex sympathetic dystrophy (RSD)

30
Q

Complex Regional Pain Syndrome- type 2

A

associated with nerve lesions formerly called causalgia

31
Q

Complex Regional Pain Syndrome- likely the results of

A

peripheral sensitization

32
Q

Myofascial Trigger Points

A

~Localized point pain generally in fascial covering of muscle or within muscle
~have been related to localized peripheral sensitization and axon reflexes

33
Q

Where do 1° nociceptive afferents synapse?

A 
in the dorsal horn of the spinal cord, specifically in:
~Posteriomarginal nucleus
~Substantia gelatinosa
~Base of dorsal horn (lamina V)
~Some in ventral horn
34
Q

What type of axon fibers go to all areas

A

Neurons in all areas receive input from C fibers

35
Q

What type of axon fibers go to postero-marginal nucleus

A

receive Ad afferents

36
Q

What type of axon fibers go to lamina V

A

~receive Ad afferents

~receive both nociceptive and low-threshold touch (Ab) input are referred to as wide, dynamic-range neurons (WDRNs)

37
Q

major 1° afferent excitatory transmitters on to central nervous system neurons are

(2-4)

A

~glutamate (glut)
~substance P (SP)
~calcitonin gene related peptide (CFRP) and adenosine triphosphate (ATP) have been discovered to modulate 1° afferent input

38
Q

Primary afferent released Glutamate (glut) binds to

A

AMPA/KA receptors

39
Q

Primary afferent released Glutamate (glut) produce

A

fast EPSPs seen in post-synaptic neurons

40
Q

Primary afferent released Substance P (SP) produces and activates

A

produces slow EPSPs and actives 2nd messenger systems in the post-synaptic cells

41
Q

CFRP and ATP also appears to activate

A

2nd messenger intracellular systems

42
Q

GABA produces

A

both pre-synaptic and post-synaptic inhibition at these primary afferent terminals

43
Q

Serotonin (5-HT) and enkephalins (ENK) produce

A

post-synaptic inhibition

44
Q

A number of agents locally released by glial cells can

A

~increase presynaptic neurotransmitter release

~increase post-synaptic excitability

45
Q

allodynia may develop in an area where (and causes)

A

~there is no apparent peripheral inflammation

~painless stimuli are now experienced as painful

46
Q

allodynia is the result of

A

altered processing by of non-nociceptive input to wide, dynamic-range neurons (WDRN)

47
Q

central sensitization- suggested mechanism involves

A

~inputs to these wide, dynamic-range neurons
~input to WDR neurons through AMPA receptors from Ab afferents is minimal
~NMDA receptors for glutamate are blocked by the action of Mg++ ion

48
Q

central sensitization- activity of nociceptors is

A

~elevated and/or prolonged the Mg++ ion blockage is removed

49
Q

central sensitization- the activation of both AMPA and NMDA receptors causes

A

the non-nociceptive Ab fibers to activate pain pathways

50
Q

central sensitization- Ordinarily painless stimuli are experienced as ——– (why?)

A

**PAINFUL
~a negative from of synaptic plasticity that has resulted in the altered processing of non-nociceptive input to wide, dynamic-range neurons (WDRN)
~the result of pain now arising from non-nociceptive stimuli

51
Q

the nociceptive signals are relayed ____ by the ____ system

A

rostrally by the spinothalamic system – specifically by the lateral spinal thalamic tracts

52
Q

the nociceptive signal- many divide this pain pathway up into two subdivisions

A

the neospinothalamic component and the paleospinothalamic component

53
Q

the nociceptive signal- neospinothalamic component is composed of

A

neurons innervated by Ad afferent fibers.

54
Q

the nociceptive signal- neospinothalamic component signals travel to

A

VPL of the thalamus via anterolateral pathway (spinothalamic) and to 1° somatosensory cortex

55
Q

the nociceptive signal- neospinothalamic component mediates

A

~fast pain

~sharp, well-localized, rapidly perceived pain

56
Q

the nociceptive signal- paleospinothalamic component is sometimes referred to as

A

Paramedial ascending system- PAS

57
Q

the nociceptive signal- paleospinothalamic component involves neurons actived by

A

the unmyelinated C primary afferent fibers

58
Q

the nociceptive signal- paleospinothalamic component rise through the

A

~ascending pathways initially rise in the lateral spinothalamic pathway

59
Q

the nociceptive signal- paleospinothalamic component projects to

A

~brainstem
~hypothalamus
~midline thalamus
~cingulate cortex

60
Q

the nociceptive signal- paleospinothalamic component mediates

A

~affective slow pain

~poorly localized, emotional content of pain

61
Q

What does Antidromic mean?

A

An antidromic impulse in an axon refers to conduction opposite of the normal (orthodromic) direction[citation needed]. That is, it refers to conduction along the axon away from the axon terminal(s) and towards the soma.
(wikipedia)

62
Q

what does denude mean

A

strip (something) of its covering, possessions, or assets; make bare.

(so a denuded axon is probably an axon stripped of its myelin or something like that).

63
Q

what is reflex sympathetic dystrophy?

A

RSD is the former name for CRPS type 1 (lacks nerve lesions)

64
Q

what is causalgia?

A

the former name for CRPS type 2 (nerve lesions present)

65
Q

CFRP

A

calcitonin gene related peptide (CFRP)

one of the neurotransmitters that modulate 1* afferent input to the CNS

PHTH 7303 Neuro (89 decks)

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