Lecture 18 - Autonomic Nervous System

Question 1

What are the divisions of the autonomic nervous system and differentiates them?

L18 S3

Answer 1

Sympathetic:

• T1-L2
• synapse with large ganglia

Parasympathetic

• CN 3, 7, 9, and 10
• S2-4
• synapse with microscopic ganglia

Question 2

What are the components of the thoracic sympathetic trunk?

L18 S6

Answer 2

Cervical ganglia:

• superior
• middle
• inferior

Thoracic ganglia:
-12 pairs

Question 3

Describe the path of the thoracic sympathetic nerves supplying the thoracic viscera.
What are the functions of these nerves?

L18 S7

Answer 3

Preganglionic supply:
-T1-5

• > Ganglionic supply:
• synapse in cervical ganglia (superior, middle, and inferior)
• synapse in T1-5 paravertebral ganglia
• > Postganglionic
• cardiopulmonary splanchnic nerve

Function:

• coronary artery dilation
• increase heart rate
• bronchodilation

Question 4

Describe the path of the thoracic sympathetic nerves supplying the abdominal viscera (splanchnic nerves).

L18 S9-11

Answer 4

Preganglionic supply:
-T5-12

• > Ganglionic supply:
• all synapse in prevertebral ganglia

-> Postganglionic nerves:
-greater splanchnic nerve (T5-9)
—celiac ganglia (celiac and hepatic plexuses
-lesser splanchnic nerve (T10-11)
—superior mesenteric ganglia
-least splanchnic nerve (T12)
—aorticorneal ganglia

Question 5

What organs are supplied by each of the splanchnic nerves?

L18 S11

Answer 5

Greater splanchnic nerve:
-celiac plexus
—stomach, duodenum, ileum, jejunumm, spleen, pancreas, gall bladder, kidneys, suprarenal glands
-hepatic plexus
—liver

Lesser splanchnic nerve:
-superior mesenteric ganglia
—liver

Least splanchnic nerve:
-aorticorenal ganglia
—kidneys, suprarenal glands

Question 6

What is the path of the vagus nerve?

L18 S18

Answer 6

• parallel to esophagus (left and right)
• anterior posterior vagal trunks (from left and right respectively)
• posterior to root of lungs
• through diaphragm with esophagus
• becomes gastric nerve

Question 7

What branches are present from the vagus nerve?

L18 S18

Answer 7

• cardiac branches
• pulmonary branches
• esophageal branches
• left recurrent laryngeal nerve (behind aorta left of ligamentum arteriosum)
• right recurrent laryngeal nerve (behind subclavian artery