Sympathetic ganglion
From Wikipedia, the free encyclopedia
Sympathetic ganglia are the ganglia of the sympathetic nervous system. They deliver information to the body about stress and impending danger, and are responsible for the familiar fight-or-flight response. They contain approximately 20000–30000 nerve cell bodies and are located close to and on either side of the spinal cord in long chains.
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[edit] Anatomy
[edit] Sympathetic chain ganglia
The bilaterally symmetric sympathetic chain ganglia, also called the paravertebral ganglia, are located just ventral and lateral to the spinal cord. The chain extends from the upper neck down to the coccyx, forming the unpaired coccygeal ganglion. Preganglionic nerves from the spinal cord synapse at one of the chain ganglia and the postganglionic fibre extends to an effector, typically a visceral organ in the thoracic cavity.
[edit] Collateral ganglia
Neurons of the collateral ganglia, also called the prevertebral ganglia, receive input from the splanchnic nerves and innervate organs of the abdominal and pelvic region. These include the celiac ganglia, superior mesenteric ganglia, and inferior mesenteric ganglia.
[edit] Additional images
The thoracic aorta, viewed from the left side.
Scheme showing structure of a typical spinal nerve. Note: gray and white rami are mislabeled--the gray ramus contains post ganglionic sympathetic nerves; the white ramus contains preganglionic sympathetic nerves.
Transverse section of human embryo eight and a half to nine weeks old.
