통증(Pain) & 통각(Nociception)

말초 통각신경

통각신경 (Nociceptors)

1. Thermal Nociceptors: Aδ fiber, > 45°C or < 5°C

2. Mechanical Nociceptors: Aδ fiber, 기계적 자극
3. Polymodal Nociceptors: C fiber, 기계,화학,온도자극
4. 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

• 

Receptor Sensitization

Spinal Dorsal Horn

Proximal End (Central Terminal)

• 

Referred Pain

Dorsal Horn Synapses

척수후각 내 TRPV1!! 거기서 뭐 해??

• 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

Dorsal Column System & Spinothalamic Tract

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

진통제