===== 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**.

==== Location ====
  * 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**

==== Function ====
  * 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)

==== Organization ====
^ 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 |

==== Clinical Relevance ====
  * **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

==== Related Topics ====
  * [[nervous_system:sympathetic_nervous_system]]
  * [[neuroanatomy:autonomic_nervous_system]]