Final: Unit VII--Sympathetics Flashcards
(113 cards)
Where are cell bodies located for preganglionic sympathetic neurons?
lateral horn or cord levels T1-L2 or L3
How do the preganglionic sympathetic neurons exit the cord?
in anterior rootlets
What do the preganglionic sympathetic neurons follow as they exit the cord?
anterior primary ramus
When the preganglionic sympathetic neurons exit the anterior primary ramus, what do they enter and how?
enter sympathetic trunk via white ramus communicans
Where do most preganglionic sympathetic neurons synapse?
on postganglionic cells in ganglia of sympathetic trunk
What will some preganglionic sympathetic neurons do that are not synapsing in the sympathetic trunk?
they pass THROUGH the sympathetic trunk and are carried in splanchnic nerves–> to synpase in prevertebral plexuses ass. w/ abdominopelvis viscera
What main NT do preganglionic sympathetic fibers release?
ACh
What does the sympathetic trunk consist of?
two paravertebral columns of interconnected ganglia
What can fibers do once they enter the sympathetic trunk?
ascend or descend
Where does the sympathetic trunk extend from?
superior cervical ganglion–> to ganglion impar (inferiorly)
(ganglion impar is on ant. side of coccyx)
How many ganglia are usually in each sympathetic trunk? How many per level?
21 or 22 (21 if combine Inf. Cervical and Superior most thoracic ganglia = Stellate Ganglion) C--> 3 T--> 11 L --> 4 S--> 4
Describe the path of the sympathetic trunk in the cervicals, thoracic, and lumbar, sacral, and coccyx areas.
Cervicals–> posterior to carotid sheath
Upper Thoracic–> anterior to necks of ribs
Lower Thoracic/Lumbars–> more medially located and lateral aspect of VBs
Sacrum–> lies on anterior aspect
Coccyx–> joins on anterior side as ganglion impar
What does the cervical sympathetic trunk lies between?
the carotid sheath and longus colli and capitis muscles
T/F. All levels of the cervical sympathetic trunk have communication with white rami communicans.
FALSE– (b/c that carries preganglionic sympathetic fibers and sympathetics are T1-L2 cord levels)
Are gray ramus communicans associated with cervical nerves?
Yes; typically 7 b/c superior most gray ramus communicans communicates with loop b/w C1 and C2 in cervical plexus
(so each Cervical spinal nerve has communication with them)
How many cervical ganglia are there usually?
three 1. Superior Cervical ganglion 2. Middle Cervical ganglion 3. Inferior Cervical ganglion ~~inferior may fuse with first thoracic ganglion to form stellate ganglion
If present, what forms the Stellate ganglion?
inferior cervical ganglion and first thoracic ganglion
Which one is the largest of the cervical ganglion?
Superior cervical ganglion
What is the Superior cervical ganglion formed by the union of?
the upper four cervical ganglia
What level is the Superior cervical ganglion located at? What is it between?
C2-C3; b/w carotid sheath and longus capitis muscle
How are the postganglionic sympathetic fibers distributed from the superior cervical ganglion?
Anterior Branch
Medial Branch
Lateral Branch
Which of the three branches at the Superior Cervical ganglion carry the gray rami communicans? What do they communicate with?
Lateral Branches
Communicate with:
- anterior primary rami of C1-C4
- CN IX, X, XII
What do the medial branches off the superior cervical ganglion travel to?
(travel directly to visceral structures)
- larynx
- pharynx
- heart–> called “Superior Cardiac Nerves”–> as efferent info ONLY (diff from ones ass. with CN X carrying pregang. parasym.)
Where do the superior cardiac nerves carrying postganglionic sympathetic fibers come from? What type of info do they carry?
the medial branch off the superior cervical ganglion
carry Efferent info ONLY