pain Flashcards
transduction, transmission, perception and modulation of pain definition
- TRANSDUCTION
Noxious (potentially harmful) stimuli translated into electrical activity at sensory nerve endings
TRANSMISSION
Propagation of impulses along pain pathways
PERCEPTION
Discrimination/ affect / motivation
MODULATION
Positive and negative modulation occurs
difference between pain and nociception
Pain is created in the brain in response to nociception - must have emotional element
The activation of neurons to encode noxious stimuli
capsaicin activates…
TRPV1
trpv1 can be activated by
capsaicin or heat
trpm8 can be activated by
cool or menthol
which neurones are nociceptibe
C and A delta
nav 1.7 mutations consequences (2)
Congenital insensitivity to pain (CIP): loss of function
Inherited erythromelalgia (IE): gain of function
Congenital insensitivity to pain with anhidrosis (CIPA): which mutatation
TRKa
C and A delta synapse where in dorsal horn
Laminae 1 and 2
what neurones soft touch
A beta
what is different between A delta and C synapse pattern
C has interneurone
where do A beta synapse in the dorsal horn
laminae 3-5
where do first order spinothalamic neurones decussate
anterior comissure
where is the emotional part of pain derived
Anterior cingulate cortex
where do lateral 3rd order spinothalamic neurones go
mediodorsal nucleus of the thalamus (MDvc) which innervates anterior cingulate cortex (ACC) [emotion/motivation].
2- posterior thalamus (VPI and VMpo) which innervates the rostral insula [emotion, unpleasantness].
where do anterior 3rd order spinothalamic neurones go
the ventral posterior lateral (VPL) and ventral posterior inferior (VPI) nucleus of the thalamus.
which is the neospinothalamic tract
lateral
which 3 areas are most important in descendin pain modulation
PAG
locus coeruleus
rapphe nucleus
the raphe nucleus is in the
RVM
locus ceruleus and raphe nucleus are involved in descending pain modulation. how
serotonin and noradrenaline inhibit incoming nociceptive signal in dorsal horn by activiating inhibitory interneurone
allodynia vs hyperalgesai
Allodynia: a condition where pain is caused by a non-noxious (non-painful) stimulus (e.g. tickle with a feather).
Hyperalgesia: a condition where an abnormal increased pain sensitivity is caused by a noxious (painful) stimulus (e.g. hot water on sunburn).
the pain synapse is ….ergic
glatamate
which are the most common overexpresseed glutamatergic receptors in pain synapses
NMDA AMPA
what is parallel transmission in pain PNS called
ephaptic transmissino
