ANS Flashcards
the autonomic nervous system includes what 3 subdivisions?
sympathetic
parasympathetic
enteric
where are cell bodies of preganglionic ANS fibers located?
clustered in a nucleus in the CNS
in general, where are cell bodies of postganglionic ANS fibers located?
clustered in a ganglion outside the CNS
preganglionic autonomic fibers release ____ mediated by ____ receptors
Ach - nicotinic
postganglionic sympathetic fibers that innervate smooth muscle, cardiac muscle, and glands/organs release ____ mediated by ____ receptors
NE - a/B noradrenergic
postganglionic parasympathetic fibers release ____ mediated by ____
Ach - muscarinic
postganglionic sympathetic fibers that innervate peripheral BVs, sweat glands and arrector pilli muscles release ____ mediated by ____ receptors
Ach - muscarinic
where are preganglionic sympathetic cells located?
intermediolateral gray of T1-L2
preganglionic sympathetic fibers exit through the ____ and briefly join the ____ and ____
v. root
spinal n.
v. ramus
what forms the white rami communicantes?
preganglionic sympathetic fibers
(from v. ramus)
after the white rami communicantes, preganglionic sympathetic fibers enter the ____
paravertebral sympathetic ganglia
what is innervated by sympathetics from T1-T4?
head & thoracic viscera
what is innervated by sympathetics from T5-L2?
abdominal & pelvic viscera
what is innervated by sympathetics from T1-L2?
peripheral BVs, sweat glands & arrector pilli muscles of body wall & limbs
where do preganglionic sympathetic fibers synapse to supply the body wall & limbs?
sympathetic chain ganglia at the same, higher, or lower level
what forms the gray rami communicantes?
postganglionic sympathetic fibers
(to body wall & limbs)
fibers from the gray rami communicates enter into the ____
ventral ramus
postganglionic sympathetic fibers from the cervical, thoracic and lumbar ganglia reach their target via ____ and innervate…
- dorsal & ventral rami
- peripheral BVs, sweat glands & arrector pilli muscles of body wall & limbs
describe the path of preganglionic sympathetic fibers innervating the head & thoracic viscera
IML -> v. rami -> white rami communicantes -> cervical ganglia (inf, mid, sup) –< carotid/cardiac plexuses
where do preganglionic sympathetic fibers to the carotid plexus synapse?
superior cervical ganglion
where to preganglionic sympathetic fibers to the cardiac plexus synapse?
middle & inferior cervical ganglia
lesion of superior cervical ganglion (or reticular formation in medulla)
Horner’s syndrome:
- ptosis
- meiosis
- anhidrosis
- enophthalmos
preganglionic sympathetic fibers that go through the ganglia without synapsing form the ____
splanchnic nerves (greater, lesser, least, lumbar)
splanchnic nerves synapse with ____
prevertebral ganglia (coeliac, superior mesenteric, inferior mesenteric)
postganglionic sympathetic fibers from the prevertebral ganglia innervate…
abdominal & pelvic viscera: GI tract, pancreas, liver, kidney, bladder, genitalia
fibers from the splanchnic nerves that bypass prevertebral ganglia innervate the ____ which releases…
adrenal medulla
NE/E into circulation
splanchnic nerves release ____ mediated by ____ receptors
Ach - nicotinic
fibers from the prevertebral ganglia release ____ mediated by ____ receptors
NE - adrenergic
preganglionic parasympathetic cells are found in…
cranial nerves III, VII, IX, X
IML gray S2-4
name the locations of preganglionic parasympathetic cells in the brainstem
- Edinger-Westphal nucleus (III)
- Superior salivatory nucleus (VII)
- Inferior salivatory nucleus (IX)
- Dorsal motor nucleus & nucleus ambiguus (X)
preganglionic fibers from the oculomotor nerve synapse in the ____
ciliary ganglion
preganglionic fibers from the facial nerve synapse in the ____ and ____
pterygopalatine ganglion
submandibular ganglion
preganglionic fibers from the glossopharyngeal nerve synapse in the ____
otic ganglion
preganglionic fibers from the vagus nerve synapse with ____ and ____
diffuse thoracic & abdominal ganglia
postganglionic fibers from the ciliary ganglion innervate…
sphincter pupillae & ciliary muscles
postganglionic fibers from the pterygopalatine ganglion innervate…
lacrimal gland
serous & mucous glands of nasopharynx
postganglionic fibers from the submandibular ganglion innervate…
submandibular & sublingual salivary glands
postganglionic fibers from the otic ganglion innervate…
parotid salivary gland
postganglionic fibers from the diffuse ganglia innervate…
heart
esophagus
lungs
stomach
liver
gall bladder
pancreas
foregut & midgut derivatives
S2,3,4 IML column gives rise to preganglionic parasympathetic fibers which via the ____, innervate…
pelvic splanchnic nn
descending & sigmoid colon + pelvic viscera
the enteric nervous system controls the function of…
GI tract
pancreas
gallbladder
enteric sensory neurons respond to…
gut wall tension & changes to chemicals in the gut
enteric motor neurons innervate…
smooth muscle, vasculature & secretion of the gut
the enteric nervous system is composed of the ____ and the ____
myenteric (Auerbach’s) plexus
submucosal (Meissner’s) plexus
where is the myenteric plexus located?
between external longitudinal & circular smooth muscle layers
where is the submucosal plexus located?
between circular smooth muscle & mucosa
what type of sensory information does the facial nerve convey?
visceral chemosensory information about taste
what type of sensory information does the glossopharyngeal nerve convey?
info from head & neck viscera
what type of sensory information does the vagus nerve convey?
info from thoracic & abdominal viscera
all sensory information of the ANS converges at the ____
solitary nucleus
name 3 ways the solitary nucleus reacts to ANS sensory info
- direct control of ANS function by reflexes (project to X and spinal cord nuclei)
- projections to reticular formation & periaqueductal gray (regulate breathing, BP, HR, etc)
- projections to hypothalamus -> thalamus, amygdala, cingulate cortex
how does the hypothalamus exert its function?
- controlling brainstem & spinal cord nuclei that control temperature, HR, BP, respiration, feeding & metabolic rate
- endocrine release of hormones that influence ANS function
