Autonomic nervous system Flashcards
what are the 3 main subdivisions of the autonomic nervous system
1 - sympathetic nervous system (SNS)
2- parasympathetic nervous system (PNS)
3- Enteric nervous system
what are some of the similarities b/w the somatic and autonomic nervous systems
- visceral sensory fibers
- acsending pathways
- descending motor pathways
- reflexes
what is the 1 difference b/w the somatic and autonomic nervous system
Autonomic nervous system efferent fibers use a 2 neuron chain (preganglionic and postganglionic)
in the ANS system, which fibers are myelinated, and which are NOT
preganglionic fibers = myelin
postganglionic = unmyelinated
where are sympathetic ganglia located ? where are parasympathetic ganglia located ?
SNS - in CNS
PNS - near innervated organ
what nuerotransmitter is/are used in the SNS
preganglionic = Ach postganglionic = norepinephrine
what neurotransmitter is/are used in the PNS
Ach
where are preganglionic cell bodies located in the SNS, what about PNS
SNS -T1-L2
PNS-brainstem and S2-S4
if the SNS is activated, what physiological effects will it have on the cardiorespiratory system
increase heart rate, constrict vasculature, relax lungs
if PNS is activated, what effect will it have on cardiorespiratory system ?
decrease heart rate, dilate vasculature, contract lungs
if the SNS is activated what effects will it have on GI and GU systems
decrease peristalsis, constrict GI sphincters, ejaculate (shoot)
if PNS is activated, what effects will it have on GI and GU systems
increase peristalsis, relax GI sphincters, dilate penis (erection)
if SNS is activated what effects will it have on head
contract pupillary dilator, increase lacrimal and salivary gland secretion and increase viscosity
if pns is activated what effect will it have on head
contract pupillary sphincter and ciliary mm. increase secretion of lacrimal and salivary glands BUT decrease its viscosity
what CN are involved in the PNS
III, VII, IX, X
what is CN III preganglionic cell body of PNS called and where can it be found
Edinger-Westphal nucleus, found in rostral midbrain
where is CN III postganglionic cell body of PNS and what muscle does it act on
ciliary ganglion, pupillary constrictor and ciliary mm
what is the function of the ciliary muscle
accomodation of lens for near vision
what is the preganglionic cell body for CN VII of PNS and where is it found
superior salivatory nucleus, tegmentum of pons
what are the postganglionic cell bodies of CN VII of PNS , and what do they act on
pterygopalatine ganglion - nasal and lacrimal glands
submandibular ganglion - submandibular and sublingual glands
what is the preganglionic cell body of CN IX of PNS and where is it found
inferior salivatory nucleus, in the medulla
what is the post ganglionic cell body for CN IX of PNS and what does it act on
otic ganglion, parotid salivary gland
what are the preganglionic cell bodies of CN X of PNS and where are the located
dorsal motor nucleus
nucleus ambiguus
-both in medulla
where are the postganglionic cell bodies for CN X of PNS
in the walls of target tissue, dont get individual names cuz to many
where are the preganglionic cell bodies located for sacral PNS outflow
lateral horn
preganglionic SNS fibers have what 4 options after they leave the ventral root ?
1 - synapse in nearest ganglion
2 - ascend to superior cervical ganglion and head
3 - descend to lower back
4 -traverse chain and emerge as splanchnic nerves
what are prevertebral ganglia
colalteral ganglia - SNS ganglia that supply fibers to pelvic and abdominal viscera
what are the cervical ganglia
3 ganglia of SNS that take input to the head
- superior cervical ganglion
- middle cervical ganglion
- inferior cervical ganglion
what aids the cervical ganglion of the SNS to take input to the head
internal carotid artery
how do postganglionic fibers reach the head
through cervical ganglia and carotid plexus
what system has preganglionic cell bodies that project to the adrenal medulla
SNS
what is Horner syndrome
loss of SNS innervation to the face
what are the 4 characteristics of Horner syndrome
- ptosis (eyelid droop)
- miosis (small pupil)
- endopthalmos (sunken eye)
- anhydrosis (dry skin)
what does a pancoast tumor result in ?
destruction of superior cervical ganglion which takes input to head from SNS, one of the causes of Horner syndrome
what syndrome causes ones eyes to be 2 different colors
congenital horners syndrome, happens because lose SNS innervation to the face before age 2. Eye needs SNS to help generate pigment to eyes at young age
what is referred pain and how does it occur ?
when pain from viscera is felt at surface, occurs when a visceral structure is innervated by same cord level of a surface structure
what system provides primary control of secretion and innervation for the intestinal tract, bladder bladder, and pancreas
enteric nervous system
