Clinical Lecture: Peripheral Somatosensory System

Question 1

Where are the following receptors found in the skin:

(a) Meissner Corpsucles
(b) Merkel’s
(c) Pacinian Corpuscle
(d) Ruffini Endings
(e) Nociceptors

Answer 1

(a) Meissner corpuscle - below the epidermis
(b) Merkle - Epidermal dermal border
(c) Pacinian - Deep Dermis
(d) Ruffin ending - Deep Dermis
(e) Nociceptors are free nerve endings found in the Epidermis and Dermis

Question 2

What type of fibres carry pressure stimuli?

Answer 2

A-Beta

Question 3

Which receptors are rapid firing?

Answer 3

Meissner and Merkel receptors.

Question 4

What type of fibres carry temperature and pain?

Answer 4

A-delta and C fibres

Question 5

What modality do A-alpha fibres carry?

Answer 5

Proprioception

Question 6

Why does chilli affect TRPV1 ion channels?

Answer 6

Along with being ion channels, many channels like TRPV1 is ligand gated. TRPV1 is temperature sensitive. It is also activated by the capsaicin which acts as a ligand.