통증(Pain) & 통각(Nociception)
차례
통각수용기
Nociceptors
Thermal Nociceptors: Aδ fiber, > 45°C or < 5°C
- Mechanical Nociceptors: Aδ fiber, 기계적 자극
- Polymodal Nociceptors: C fiber, 기계,화학,온도자극
- Silent Nociceptors: 내장기관. 이차통증과민화, 중추감각
Nociceptive Receptors
Distal End (Peripheral Terminal)
TRP channels
The capsaicin receptor: a heat-activated ion channel in the pain pathway. Nature 1997.
Inflammatory mediator receptors
Sensitization
Spinal Dorsal Horn
Proximal End (Central Terminal)
Referred Pain
Dorsal Horn Synapses
TRPV1 in spinal dorsal horn!!??
Pre-synaptic TRPV1 function proposed in J.Neurosci 2009
Post-synaptic TRPV1 function proposed in Neuron 2012
Second-order Neurons (Interneurons & Projection Neurons)
통각과민
통각 전도로
시상
피질
통증의 정의 from International Association for the Study of Pain:
- An unpleasant sensory and emotional experience
- associated with actual or potential tissue damage,
- or described in terms of such damage.
Cingulate cortex, Insular cortex are active during pain perception.
the Pain Chronicles by Melanie Thernstrom
내인성 통증조절 기전
전구체 |
Peptide |
Receptor |
POMC |
β-endorphin |
μ/δ |
Endomorphin-1 |
μ |
|
Endomorphin-2 |
μ |
|
Proenkyphalin |
Met-enkephalin |
δ |
Leu-enkephalin |
δ |
|
Prodynorphin |
Dynorphin A |
κ |
Dynorphin B |
κ |
|
Pro-orphanin FQ |
Orphanin FQ |
Orphan receptor |
진통제
/Pain /SensorySystem /Touch |