ANS Flashcards
How are the accessory spinal nerves routed?
What are the greater splachnic nerves and what do they innervate?
The greater splanchnic nerves originate from T5-T9 spinal nerves and synapse into the prevertebral celiac ganglia. Postganglionic axons from these ganglia innervate stomach, abdominal blood vessels, liver, gallbladder, part of the pancreas and small intestine.
What are the lesser splachnic nerves and what do they innervate?
The lesser splanchnic nerves originate from T9-T11 spinal nerves and project to prevertebral superior mesenteric ganglia. Postganglionic axons from these ganglia innervate the large intestine.
What are the lumbar splachnic nerves and what do they innervate?
Lumbar splanchnic nerves that extend from L1-L2 spinal nerves terminate to the inferior mesenteric ganglia. Postganglionic axons from these ganglia project to and innervate the distal part of the large intestine, rectum, kidneys, urinary bladder, gonads and external genitalia.
What is craniosacral outflow?
The outflow of the parasympathetic nervous system.
Cranio: Cranial nerves III, VII, IX, and X
Sacaral: S2-S4
Cranial nerves of the parasympathetic NS:
III - Oculomotor nerve - ciliary ganglion - eye
VII - Facial nerve - pterygopalantine ganglion or submandibular ganglion
IX - Glossopharyngeal nerve - otic ganglion
X - Vagus nerve - innervates heart, lungs, digestive organs to the left colic flexure
CN’s III, VII, and IX route to ganglia that regulate secretions
What portion(s) of the large intestines do the pelvic sphlacnic nerves innervate?
The left colic flexure downward to rectum
Damage to the sacral spinal nerve roots results in fecal/urinary incontinence and impotence
Splachnic nerve
Hirschsprung’s disease
The sacral (and some cases vagal) fibers do not innervate portions of the hindgut because of faulty migration of neural crest cells (deficit of myenteric and Meissner plexuses).
Bowel does not dilate - sympathetic innervation is not challenged by pNS
What innervates the intestines all the way to the left colic flexure?
CN X (vagus nerve)
In what fibers of the pNS are there sNS fibers present?
sNS fibers are present in all elements of the pNS
What aspects of the pNS contain both somatic and visceral sensory fibers?
All elements of the pNS contain somatic and visceral sensory fibers
What element(s) of the nervous system contains pNS motor fibers?
Sacral outflow
What element(s) of the NS do not contain somatic motor fibers?
Cutaneous branches
Phrenic nerve
Type of nerve fibers
Sympathetic
C3, 4, and 5 keeps the diaphragm alive
