last updated 19-03-2024

Peripheral stimulation of nociceptors

Peripheral stimulation of nociceptors

In order to explain how nociceptors are activated by certain stimuli, the example of a cut in the skin is chosen here. Due to the cut, cells are damaged in the skin and a blood vessel was hit. The damaged cells release potassium ions and prostaglandins, which are strong pain stimuli for the nociceptors.

Bradykinin and lactic acid arrive from the bloodstream and are also able to stimulate the nociceptor. Another stimulator is serotonin, which is synthesised by the platelets. When an inflammation occurs at the damaged site, immune cells like mast cells will arrive and produce acids and histamine. The acidic environment and histamine stimulate the nociceptors as well.

1

Aδ-neurons are sensitive to pressure, but cannot translate the stimuli into pain. 

2

Nociceptors are unspecialised structures; they are simple free nerve ends.