The dorsal root ganglion (DRG) contains the cell bodies of primary afferent sensory neurons that transmit information from peripheral receptors to the central nervous system[1]. These neurons are critical for detecting touch, temperature, pain, and proprioception[2]. In neuropathic pain conditions, DRG neurons undergo pathological changes that contribute to chronic pain states[3]. This page explores the anatomy, function, and mechanisms by which DRG neurons contribute to neuropathic pain, with particular relevance to neurodegenerative diseases.
| Taxonomy | ID | Name / Label |
|---|---|---|
| Cell Ontology (CL) | CL:4023189 | parasol ganglion cell of retina |
The DRG are clusters of neuronal cell bodies located along the dorsal roots of spinal nerves[4]:
DRG neurons are classified by their morphological and functional properties[8]:
| Type | Diameter | Function | Markers |
|---|---|---|---|
| Aβ-large | 30-70 μm | Touch, pressure | NF200, TrkC |
| Aδ-medium | 10-30 μm | Temperature, sharp pain | CGRP, IB4 |
| C-small | 0.5-5 μm | Dull pain, itch | IB4, TRPV1 |
Primary afferent neurons release various neurotransmitters[9]:
Nerve injury leads to dysregulation of multiple ion channels[14]:
Satellite glial cell activation plays a critical role[23]:
Nerve injury induces mitochondrial dysfunction in DRG neurons[27]:
DRG involvement in ALS includes[31]:
DRG neurons are primary targets in diabetes[35]:
Multiple chemotherapeutics target DRG neurons[39]:
Emerging evidence links PD to sensory dysfunction[43]:
Several drug classes target DRG mechanisms[46]:
| Drug Class | Target | Example |
|---|---|---|
| Sodium channel blockers | Nav1.7/1.8 | Lidocaine, carbamazepine |
| Calcium channel blockers | Cav2.2 | Ziconotide |
| TRPV1 antagonists | TRPV1 | Capsazepine |
| Cytokine inhibitors | IL-1β, TNF-α | Etanercept |
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