Neuro - Nociception Flashcards
where are the somas of all somatosensory neurones located
dorsal root ganglia
where do the 2 branches of the soma depart to
one to the PNS
other to CNS
where do 1st order neurones enter
into the dorsal root and joins the dorsal column
what are examples of what 1st order neurones detect and where are they terminated
pain/temperature fibre
dorsal root
what are 1st order neurones classified as and why
pseudounipolar
2 axon branches
features of a Aβ neurone
touch
6-12micrometers
35-75m/s
features of Aδ
pain and temperature
free nerve endings
1-5 micrometer diameter
5-30m/s
features of C neurones
pain, temperature and itch
free nerve endings
0.2 - 1.5 micometer
0.5 - 2 m/s
what contains a complete representation of the somatic sensory periphery
thalamus
where is are 2nd order neurones terminated
thalamus
what does a painful heat cause (>43 degrees C)
TRPN1 channels open in C fibre endings
what mediates the affective-motivational aspect of the brain
multiple signals from the antolateral system to the reticular formation of the midbrain
features of Aβ - fast pain neurones
small and thinly myelinated
10% nociceptive fibres
sharp/quick pain
mechanical stimuli
afferent portion of the reflex arc
features of C fibres - slow pain
small and unmyelinated
90% of afferent sensory fibres
mechanical/thermal and chemical
potentially long term - aching, deep, visceral pain
what are the inflammatory mediators after tissue damage
prostaglandins
bradykinin
substance P
