Brainscape's Knowledge GenomeTM

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


See full index

PMCOL 412 > PAIN II > Flashcards

PAIN II Flashcards

1
Q

Pathway to brain

A

Most axons of lamina I and IV projection neurons cross midline and ascend in the anterolateral quadrant of SC

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

Terminations of pain pathways and their tract

A
  • Reticular Formation (Spinoreticular Tract)
  • Midbrain (Spinomesencephalic Tract)
  • Thalamus (Spinothalamic Tract)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Spinoreticular Tract projects to

A

reticular neurons (alerts to pain) in brainstem

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

Does the Spinoreticular Tract have topographical organization

A

NO–Lacks topographical organization

reticular neurons have wide receptive field

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

What aspects of pain are signalled by the Spinoreticular Tract

A

general aspects of pain perception

e.g. alerts onset of pain–doesn’t say what or where BUT ALERTS to pain

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

reticulothalamic tract

A

Projection from reticular formation to thalamus (second to the spinoreticular tract)

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

Spinomesencephalic tract–projects to

A

midbrain periaqueductal gray matter (PAG)

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

Role of the PAG

A

interaction between ascending pain signals and descending analgesic information from `emotional centres’ such as amygdala

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

Spinomesencephalic tract–additional projections

A

to hypothalamus (lateral parabrachial area), nucleus of solitary tract and amygdala

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

Role of Spinomesencephalic tract

A

Autonomic, affective and neuroendocrine responses to pain

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

Spinothalamic tract: 2 divisions

A

Lateral–NEW; to VPL

Medial–OLD: to intralaminar thalamic neurons

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

Spinothalamic tract (lateral division) is ___ (new or old)

A

NEW; Phylogenetically recent = neospinothalamic tract

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

Lateral Spinothalamic tract projects to

A

ventroposteriolateral (VPL) nucleus of thalamus–only 10% of these neurons are nociceptive

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

Role of the lateral spinothalamic tract

A

somatotopically organized

localization and discriminative aspects of pain

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

Further projections of the lateral spinothalamic tract

A

somatic sensory cortex and parietal lobe

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

Spinothalamic tract (medial division) is ___ (new or old)

A

OLD; Phylogenetically old = paleospinothalamic tract

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

Medial Spinothalamic tract projects to

A

intralaminar thalamic neurons

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

Medial Spinothalamic tract organization and input

A

NOT somatotopic organization

input comes from dorsal horn cells have large receptive fields

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

Further projections of the Medial Spinothalamic tract

A

project widely to association and prefrontal cortex

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

Role of the Medial spinothalamic tract

A

affective and alerting aspects of pain

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

This tract alerts you to pain

A

Spinoreticular tract

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

This tract is repsonsible for the autonomic, affective and neuroendocrine responses to pain

A

Spinomesencephalic tract

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

This tract is somatotopically organized and is responsible for localization and discriminative aspects of pain

A

Lateral division of the spinothalamic tract

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

This tract has affective and alerting aspects to pain and projects to the prefrontal and association cortices

A

Medial division of the Spinothalamic tract

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

Pain Matrix is made up of:

A

ACC (anterior cingulate)
PFC
Insular cortex
Somatosensory cortex

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

Role of pain matrix (higher centers)

A

Imparting salience and valence of noiceptive stimuli

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

If pain signals tissue damage, why have endogenous analgesic mechanisms?

A

Central Mechanisms to suppress pain have significant survival value
Stop the pain while you escape a dangerous situation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Endogenous mechanisms of analgesia need to have ____ so they don’t inhibit pain’s survival value

A

HIGH threshold of activation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Endogenous opioids

A 
Met Enkephalin (delta),
Leu Enkephalin, (delta ) 
Dynorphin, (kappa)
Endorphin, (mu)
Orphanin FQ (Nociceptin)
(ORL1),
Endomorphin 1 and 2 (mu)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Met Enkephalin receptor

A

delta opioid (DOR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Leu Enkephalin receptor

A

delta opioid (DOR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Dynorphin receptor

A

kappa opioid (KOR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Endorphin receptor

A

mu (MOR)

34
Q

Orphanin FQ/Nociceptin

A

ORL1

35
Q

Endomorphin 1 and 2

A

mu (MOR)

36
Q

Mechanism of opioid receptors (simple)

A

All opioid receptors are Gi/Go coupled

37
Q

How opioid receptors work (complicated mechanism)

A

Inhibit adenyl cyclase –> decreased cAMP –> activate GIRK –> hyperpolarization –> N-type Ca channels close –> less NT release

38
Q

Opioid receptors are (inhib or excit)

A

INHIBITORY (but effect depends on what type of cell they are on)
Decreased Neurotransmission

39
Q

Descending analgesic pathways (structure overview)

A

Amygdala –> PAG –> RVM –> spinal opioid interneurons

pathway held in check by tonic GABAergic inhibition in RVM and PAG

40
Q

When GABA isn’t on RVM and PAG

A

descending analgesic pathways can release endogenoys opioids to suppress pain transmission in the dorsal horn of the SC

41
Q

Under normal physiological conditions the descending analgesic pathways are held in check by

A

tonic GABAergic inhibition on PAG and RVM

42
Q

How to trigger analgesia in the descending analgesic pathway

A

electrical stim of PAG releases endogenous opioids –> these Opioids inhibit inhibitory neurons –> release the inhibition of the RVM and PAG (disinihbition) and allowing the release of endogenous opioids to suppress pain transmission = analgesia

43
Q

Two cell types in RVM (rostral ventrolateral medulla)

A

‘ON’ cells = turned on by noxious stim –> pain

‘OFF’ cells = turned off by noxious stim –>analgesia

44
Q

‘ON’ cells are _____ by noxious stimuli and ____ by opioids; effect:

A

excited by noxious; inhibited by opioids

= turn off descending pathways and allow you to feel pain

45
Q

‘OFF’ cells are _____ by noxious stimuli and ____ by opioids; effect:

A

inhibited by noxious; excited by opioids

= turn on descending analgesic pathways

46
Q

How do opioids act at the spinal dorsal horn

A

opioids act presynaptically to inhibit Ca2+ channels and reduce glutamate release from C-fibres and A-delta fibers

47
Q

Pathways of analgesia at the spinal cord via opioid interneurons

A

Descening pathways end on opioid interneuron –> opioid released onto presynaptic terminal of afferents –> inhibit Ca2+ channels (less Ca conductance) –> decreased NT release –> reduced EPSP

48
Q

How opioids worrk on post-synaptic neurons

A

opioids act to incrrase K+ conductance in post-synaptic neuron –> hyperpolarized –> decreased NT release
helps decrease firing

49
Q

Mu receptors are found in the…

A 
PAG
RVM (rostral ventral medulla)
Dorsal horn (substantia gelatinosa)
VTA
LC 
Pre-Botzinger region 
Enteric nervious system
50
Q

Effects of Mu opioid receptors in the PAG, RVM, and dorsal horn

A

analgesia

51
Q

Effects of Mu opioid receptors in the VTA

A 
reinforcing effects (dopaminergic)
ADDICTION
52
Q

Effects of Mu opioid receptors in the LC

A

somatic effects of physical dependence

LC is an autnomic centre

53
Q

Effects of Mu opioid receptors in the pre-botz region

A

respiratory depression

this area sets the resp. rhythmn

54
Q

Effects of Mu opioid receptors in the enteric nervous system

A

constipation

55
Q

Effects of opioids

A
  • Morphine, Heroin, Fentanyl etc.
  • Analgesia
  • Euphoria
  • Sedation (Narcotic)
  • Respiratory depression
  • Constipation
  • Tolerance, dependence, ‘addiction’
  • Hypotension
  • Pin point pupils (parasymp)
56
Q

Opioid Interactions with the Immune system may explain

A
  • Sweating and itching responses
  • Paradoxical hyperalgesia (more pain with inflammatory response)
  • Analgesic effect of naloxone
57
Q

How can naloxone have Analgesic effects

A

At low doses has analgesic effect likely due to inhibition of opioid effects on the immune system

58
Q

Drug addiction is:

A
  • Continued use of drugs despite serious negative consequences
  • Compulsive drug seeking activity
  • Evidence of withdrawal when drug is unavailable (usually opposite of drug effect)
59
Q

Behaviours can also be addictive because they are

A

Rewarding

Reinforcing

60
Q

Rewarding effects can be (2 possibilities)

A

positive (e.g. euphoria) or relief of negative symptoms (e.g. pain, anxiety, depression)

61
Q

Mesolimbic reward pathways

A

VTA –> NAc
VTA –> basal forebrain/amygdala
VTA –> medial PFC

62
Q

Micking or potentiating DA in the mesolimbic DA pathway is…

A

rewarding and reinforcing

63
Q

All potnetially addictive drugs produce _____ in animals

A

self administration

64
Q

Importance of natural reinforcement

A

Dopaminergic reinforcement is important biologically –promotes activities that allow you to survive and reproduce (food, water, sex, warmth)
AND drugs

65
Q

Long-term drug treatment leads to

A

tolerance and dependence/withdrawal

66
Q

Tolerance

A

need more drugs for same effect

67
Q

Dependence

A

physiologicaly only normal when drug is in system

68
Q

Animals will self stimulate _____ which activates reward pathway from ___. this is enhanced by ____.

A

Self stim medial forebrain bundle, activates VTA reward pathway
effect enhanced by addictive drugs (amphetamines, opioids, cocaine, nicotine, PCP, benzodiazepines and ethanol)

69
Q

Addicitve drugs increase ___ in the ___

A

DA in the NAc (as seen in microdialysis studies)

DA inhibits GABAergic spiny projection neurons in nucleus accumbens but how this relates to reward is unknown.

70
Q

How cocaine creates reward

A

inhibits DA reuptake (more DA –> more inhibition of spiny neurons in NAc = reward)

71
Q

How amphetamines create reward

A

reverse reuptake transporter to export DA and inhibits DA storage (so DA is pumped out not stored)

72
Q

Cocaine and amphetamine _____ increase ___ transmission. Rewarding effects can be blocked by…

A

directly; DA

Rewarding effects blocked by DA antagonists or by the DA synthesis inhibitor a-methylparatyrosine

73
Q

Opioid mechanism of reward

A

2 ways:
disinhibition of VTA (inhibit gaba interneurons –> more DA release)
Direct inhibition of spiny projection neurons in the NAc by DA (inhibition -> reward)

74
Q

Nicotine reward

A

not generally behaviourally reinfocring

Directly stimulate VTA –> DA release –> DA inhibits NAc

75
Q

Ketamine

A

effectively inhibit neurons in NAc
Blocks NMDA receptors and excitatory glut drive to spiny projection neurons (when spiny projection neurons are inhibited = addiction)

76
Q

‘On’ cell neuron type/NT type

A

GABAergic interneuron

on cells are GABAergic interneurons excited by pain –> turn off descending pathway –> allow pain perception

77
Q

‘Off’ cells function

A

pain/noxious stim –> inhibit OFF cell –> inhibit spinal inhibitory interneuron (disinhibition of pain)–> no analgesia therefore pain is felt
opioids –> excite off cell (RVM neuron) –> stimulate spinal inhib interneuron –> inhibit pain (= analgesia)

78
Q

descending analgesic pathway end on ______ which release _____ unto _____ terminals of _____
RESULT:

A

opioid interneurons, release opioids onto presynaptic terminals of afferents entering the SC
resulting in decreased Ca conductance and therefore decreased NT release

79
Q

Opioid modulation of K+

A

opioids directly interact with post-synaptic neurons in the SC –> increase K+ conductance –> hyperpol –> decrease NT release

80
Q

DA ____ (inhibits/excites) ____ (neuron type) in NAc

A

inhibits GABAergic spiny projection neurons

unsure how this relates to rewards

81
Q

Increased DA onto the Nac –>

A

inhibition of NAc spiny projection neurons = reward

82
Q

How increased DA creates reward

A

increased DA onto NAc –> da inhibits spiny projection neurons = addiction/reward

PMCOL 412 (35 decks)

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