Neurotransmitters in Pain
|
Neurotransmitter |
Role in Pain Modulation |
Mechanism of Action |
|
Glutamate |
Primary excitatory neurotransmitter; mediates nociceptive signal transmission in the spinal cord and brain. |
Activates NMDA and AMPA receptors, facilitating excitatory neurotransmission and central sensitization. |
|
Substance P |
Facilitates pain transmission and inflammation by promoting neurogenic inflammation and sensitization. |
Binds to neurokinin-1 (NK1) receptors; increases vascular permeability and pain signal transmission. |
|
Calcitonin Gene-Related Peptide (CGRP) |
Enhances pain signaling, promotes vasodilation, and contributes to migraine pathophysiology. |
Acts on CGRP receptors causing vasodilation and sensitization of nociceptors. |
|
Endorphins |
Endogenous opioids that inhibit pain signals by binding to opioid receptors. |
Activate μ, δ, and κ opioid receptors reducing neurotransmitter release and pain perception. |
Neurotransmitter Function Chart
|
Neurotransmitter |
Pain Effect |
Location |
Clinical Relevance |
|
Glutamate |
Excitatory |
Spinal cord, brain |
Target for NMDA antagonists in chronic pain |
|
Substance P |
Excitatory |
Peripheral & CNS |
Target in NK1 receptor antagonists trials |
|
CGRP |
Excitatory |
Peripheral nerves |
Target in migraine therapies (CGRP inhibitors) |
|
Endorphins |
Inhibitory |
CNS & Peripheral |
Basis of opioid analgesics |
References
- Scholz J, Woolf CJ. The neuropathic pain triad: neurons, immune cells, and glia. Nat Neurosci. 2021.
- Raja SN, Carr DB, Cohen M, et al. The revised IASP definition of pain: Concepts, challenges, and compromises. Pain. 2020.
- Stein C. Endogenous opioid peptides and receptors: from discovery to open therapeutic problems. Pharmacol Rev. 2021.
- NIH Pain Consortium. Pain Management Guidelines. 2022.