sympathetic_nuclei

The sympathetic nuclei are clusters of neuronal cell bodies located in the central nervous system, specifically within the intermediolateral cell column (IML) of the spinal cord.

  • Found in the lateral horn of the spinal cord gray matter
  • Present from T1 to L2/L3 spinal cord segments
  • Also referred to as the thoracolumbar outflow
  • Contain preganglionic sympathetic neurons
  • Axons exit via ventral roots, then enter the sympathetic chain ganglia (paravertebral) or prevertebral ganglia
  • Postganglionic neurons project to target organs:
    • Heart (↑ rate and contractility)
    • Pupils (dilation)
    • Skin (sweating, vasoconstriction)
    • Gastrointestinal tract (↓ motility)
Region Spinal Levels Role
Intermediolateral Nucleus T1–L2 Origin of preganglionic sympathetic neurons
Paravertebral Ganglia Along vertebral column Relay to postganglionic neurons
Prevertebral Ganglia Abdomen (e.g., celiac, mesenteric) Control of abdominal viscera
  • Horner Syndrome: Damage to the sympathetic pathway causes ptosis, miosis, and anhidrosis
  • Spinal cord injuries above T1 can interrupt sympathetic output
  • Autonomic dysreflexia in spinal lesions above T6
  • sympathetic_nuclei.txt
  • Last modified: 2025/07/01 11:01
  • by administrador