Flashcards in Autonomic Nervous System Deck (18):
What does the autonomic nervous system innervate?
Smooth muscle, cardiac muscle, glands and adipose tissue
The sympathetic division of the ANS is also known as what?
The thoracolumbar outflow
The parasympathetic division of the ANS is also know as what?
The craniosacral outflow
In what part of a spinal cord transverse segment are sympathetic neuronal cell bodies found?
The IML (Intermediolateral) Cell Column (in the lateral horn)
Sympathetic cell bodies are found in the vertebral column between what vertebral bodies?
T1 and L2
What are the three places where preganglionic sympathetic fibers can synapse?
1) A paravertebral ganglion in the sympathetic chain, 2) A prevertebral ganglion, or 3) On chromaffin cells in the adrenal medulla
What is abnormal about chromaffin cells of the adrenal medulla amongst postganglionic sympathetic cells?
They release their contents into bloodstream instead of onto target organ (also they are not located in paravertebral or prevertebral ganglia)
How do sympathetic cells that synapse in prevertebral ganglia get there?
By passing through a paravertebral ganglion without synapsing (and then traveling through a splanchnic nerve)
What relays nerve fibers from paravertebral ganglia to prevertebral ganglia?
What are the four things a preganglionic sympathetic cell can do once entering the sympathetic chain?
1) Ascend the chain and synapse in a higher paravertebral ganglion, 2) Descend the chain and synapse in a lower paravertebral ganglion, 3) Synapse in the ganglion at its level, 4) Continue through a splanchnic nerve (usually to a prevertebral ganlgion)
Do splanchnic nerves innervate skeletal muscle, viscera, both or neither?
Is a splanchnic nerve which is carrying postganglionic sympathetic fibers carrying neurons that have synapsed in a prevertebral ganglion or not?
Yes, they have synapsed (you know this because you were told it was POSTganglionic)
Which cranial nerves carry parasympathetic neurons out of the brainstem (give numbers and names)?
Oculmotor (3), Facial (7), Glossopharyngeal (9), Vagus (10)
How do sacral parasympathetic neurons exit the spinal cord?
Ventral rami of spinal nerves S2, S3, S4, and then branch to form pelvic splanchnic nerves
Give the four parasympathetic ganglia of the head and which cranial nerve targets each
Otic (CN9), Submandibular (CN7), Pterygopalatine (CN7), Ciliary (CN3)
Where do parasympathetic preganglionic neurons that do not synapse on a ganglion in the head synapse?
On a postganglionic neuron in or near the wall of the target organ
What type of nerve fibers do the pelvic splanchnic nerves carry?
Preganglionic parasympathetic fibers which will synapse in or near the wall of the organ they innervate