Pain perception

Question 1

How are the free nerve endings that detect injury in the skin called?

Answer 1

Nociceptors

Question 2

Which conformation do Nociceptors have?

Answer 2

They are free nerve endings in the skin.

Question 3

Name the 4 types of nociceptors, which type of pain they detect, and which type of nerve fibre they carry to send their information

Answer 3

TRPV1 - Transient Receptor Potential Vanilloid type 1 - delayed burning pain (chilli peppers) - C fibre (slow)
TRPM3 - Transient Receptor Potential type M3 - ready burn (burning object) - Adelta fibre (fast)
CMR1 - Cool-Menthol receptor 1 delayed sense of coolness - C fibre
Nppb - itching sensation -C fibre.

Question 4

What is the name of the specific ion channel that neurotransmitter used to transmit “mechanical” pain use the most?

Answer 4

Nav1.7

Question 5

What is Neurophatic pain or Neuralgia and what is it an example of?

Answer 5

Neuralgia or Neurophatic Pain is the feeling of pain for a missing limb, and it is an example of neuronal plasticity

Question 6

Do fibres of the Anterolateral/Spinothalamic system, once they have entered the central nervous system through the dorsal root ganglion, cross the midline immediately?

Answer 6

yessa, unlike the fibers of the Dorsal Column system :)

Question 7

How is the pathway of nerve fibers taking the pain information from the peripheral system to the cingulate cortex called? (2 name options, one starts with A and the other with S)

Answer 7

Anterolateral or Spinothalamic nervous system

Question 8

What are the steps of the Anterothalamic Spinothalamic nervous system?

Answer 8

1. Nerve fibers (C and Adelta) synapse on other fibres like them
2. C and Adelta fibres enter the Central nervous system through the dorsal root ganglion and cross the midline
3. Throughout the Brainstem, the fibers send information to centers responsible for pain reaction (eg reticular formation in the Pons responsible vocalisation)
4. In the thalamus, fibres synapse on the Thalamic nuclei
5. The thalamic nuclei synapse on the cortical cells of S1 and cingulate cortex.

Question 9

What is ipsilateral loss

Answer 9

The loss of sense of touch or perception of pain on the same side of the body where a patient was injured

Question 10

What is contralateral loss

Answer 10

The loss of sense of touch or perception of pain on the opposite side from where a patient was injured.

Question 11

What are the three carrier cells (this term is MADE UP don’t use it thx) of the anterolateral/spinothalamic nervous system?

Answer 11

Adelta fibers and C fibers -> Adelta fibres and C fibres (tricked you there, but the synapse are three!) -> Thalamic nuclei