Innervation of the Abdominal Viscera Flashcards Preview

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Flashcards in Innervation of the Abdominal Viscera Deck (15):

What are the three branches of the lower splanchnic nerves that innervate the abdominal viscera (give their respective spinal levels as well)

Greater Splanchnic Nerve: T5-T9 Lesser Splanchnic Nerve: T10-T11 Least Splanchnic Nerve: T12


What lower thoracic splanchnic nerve is the main source of presynaptic nerve fibers innervating the abdominal viscera?

Greater Splanchnic Nerve (T5-T9)


The lower thoracic splanchnic nerves convey presynaptic sympathetic fibers to what adominal structures?

Celiac, Superior Mesenteric, & Prevertebral Sympathetic Ganglia


The lumbar splanchnic nerves covey presynpatic sympathetic fibers to what abdominal structures?

Intermesenteric, Inferior Mesenteric, and Superior Hypogastric Plexus


What are the two main divisions of parasympathetic innervation to the GI system?

1) Anterior and Posterior Vagal Trunks 2) Pelvic Splanchnic Nerves


Anterior and Posterior Vagal Trunks: 1) Continuation of ? 2) Function ?

1) Right and left Vagus nerves; respectively 2) Parasympathetic innervation of the smooth muscle and glands up to the Left colic flexure


Pelvic Splanchnic Nerves: 1) Derived from 2) Function

1) Anterior Rami of S2-S4 2) Parasympathetic innervation from left colic flexure to the remainder of the GI system


Pelvic Splanchnic nerves: 1) Characteristics 2) Derived from 3) Pathway/Contribution

1) Not associated with sympathetic trunk 2) Derived from anterior rami of spinal nerves S2-S4 3) Presynaptic parasympathetic nerve fibers to inferior hypogastric plexus


Enteric Nervous System: 

1 &2) Two Principle Components 

A) Their function

B) Sympathetic or Parasympathetic

1) Myenteric (Auerbach's) Plexus A) Motility B) Parasympathetic 

2) Submucosa (Meissner's) Plexus A) Secretion/Absorption B) Sympathetic 



Nerves of Superior Mesenteric Plexus: 

1) Sympathetics

2) Parasympathetics

1) Greater and lesser splanchnic Nerves & GVA pain fibers

2) Median root from celiac plexus, branch of posterior vagal trunk, GVA visceral reflex fibers 


Nerves of Inferior Mesenteric Plexus: 

1) Sympathetic

 2) Parasympathetic

1)  Lumbar ganglia of sympathetic trunk & GVA pain fibers

2) Medial root from intermesenteric plexus (continuation of vagus), GVA reflex fibers


Superior Hypogastric Plexus: 

1) Characteristics

2) Supplies

3) Sympathetics or Parasympathetics

4) Connections

1) Anterior abdominal aortic bifurcation & continuous with intermesenteric and inferior mesenteric plexuses 

2) Uteric and Testicular Plexues

3) Only sympathetics

4) Connected to inferior hypogastrix plexus via R/L Hypogastric nerves


Pain Afferents are conveyed via?

Sympathetic components to T5-L2


Reflex Afferents (information from chemoreceptors, osmoreceptors, and mechanoreceptors); these are conveyed to?

Autonomic centers in the medulla oblongata


Inferior Hyopgastric Plexus: 

1) Sympathetics

2) Parasympathetics

3) Output

1) Superior Sacral Sympathetics

2) Pelvic Splanchnics (S2-S4)

3) Visceral plexuses on walls of pelvic viscera