Dorsal root ganglion

The most common type of sensory ganglion is the dorsal root ganglion or DRG or posterior root ganglion. Ganglia are the "cell bodies of neurons with axons that are sensory endings in the periphery, such as in the skin, and that extend into the CNS through the dorsal nerve root." Ganglia is plural of ganglion. Generally speaking, each vertebra of the spinal column has both afferent (sensory) and efferent (effector) nerves emerging from inside the spine, and the dorsal/posterior side of the spine is where the afferent nerve emerges. Each afferent nerve has a bulge containing the cell bodies of the neurons in the afferent nerve. This bulge is called a dorsal root ganglion.

The neuron is parted of two parts:


 * 1) Dendrite receives the information and sends it to the Perykaron (cytoplasm which is around the nucleus).
 * 2) Axon takes this information and sends forward.

In human disease
Ganglionitis is inflammation of a nerve ganglion. The dorsal root ganglia can become inflamed causing severe pain and other symptoms. Conditions that can cause dorsal root ganglionitis include trauma, sciatica, compressive neuropathy, herniated disc, spinal stenosis, peripheral neuropathy, meningitis, and spinal infections, including Herpes simplex virus 1.

ME/CFS
Inflammation of the dorsal root ganglia (ganglionitis) has been found in the autopsies of several very severely ill myalgic encephalomyelitis patients including Lynn Gilderdale, Sophia Mirza and Merryn Crofts.

Sjogren's syndrome
Thirteen Sjögren's syndrome patients with autonomic dysfunction were found to have lymphocytic (T‐cell) infiltration in the dorsal roots and ganglia. Electrophysical studies also found involvement of the dorsal root ganglia. Antiganglion autoantibodies have been detected in patients with sensory neuronopathy.

Chronic pain
Changes in microRNA expression in the dorsal root ganglia are consistently found in pre-clinical chronic pain patients, leading to clinical trials targetting dorsal root ganglia stimulation as a potential treatment for chronic pain.

Learn more

 * 2006, Inflammatory mediators enhance the excitability of chronically compressed dorsal root ganglion neurons.
 * 2013, dorsal root ganglionitis: Kay Gilderdale writes of her late, severely affected, daughter:


 * 2014, Inflammation in dorsal root ganglia after peripheral nerve injury: Effects of the sympathetic innervation


 * 2015, Herpes Simplex Virus Type 1 Dorsal Root Ganglionitis in a 34 Year Old Male With Occipital Neuralgia Refractory to Medical and Radiofrequency Ablation Therapies: A Clinicopathological Report and Literature Review (P1.293)
 * 2015, Dorsal Root Ganglionitis - infection of inflammation?
 * Histology Photomicrographs
 * Shotgun Histology Dorsal Root Ganglion - Video
 * Slide 42 - Dorsal Root Sensory Ganglion - Video explanation of histology slide