Pain and Thermosensation Flashcards
What are the three forms of pain?
Nociceptive
Inflammatory
Pathological
What are nociceptors?
Specific primary sensory afferent neurones that are activated by noxious stimuli
What are the main subtypes of nociceptor?
A delta fibres
C fibres`
“First/fast” pain is mediated by which nociceptor?
A delta fibres
“Second/slow” pain is mediated by which nociceptor?
C fibres
Explain how the peripheral terminal of a nociceptor produces an action potential
Sodium/calcium influx causes membrane depolarisation causing sodium influx and AP production
What is the function of afferent peptidergic polymodal nociceptors?
Transmits nociceptive information to the CNS within the dorsal horn
What do efferent peptidergic polymodal nociceptors do?
Release pro-inflammatory mediators (neurogenic inflammation)
What effects do pro-inflammatory mediators have?
Vasodilation
Histamine release
Nociceptor sensitisation
What is the primary neurotransmitter released by primary afferent?
Glutamate
Glutamate will excite which receptors?
AMPA
NMDA
Why does ‘referred pain’ occur?
As some visceral and skin afferents converge upon the same spinothalamic neurones
In gate control theory, which type of neurone is excited to inhibit pain?
A beta fibres
