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Flashcards in ANS Deck (33):

what does the ANS control?

voluntary or involuntary?

what type of efferent fibers does it use?

what controls the ANS? Which controls it the most?

smooth muscle, cardiac muscle, and glands



Hypothalamus and brainstem

Hypothalamus controls ANS mostly


where do we find the pneumotaxic control center?

What it the pneumotaxic control center?

Blood pressure control centers can be subdivided by function, what are these?


in the pons

area in brainstem that controls respiration

1) cardiac acceleration and vasoconstriction

2) cardiac slowing



what do you call the higher control centers for the ANS?






There are three main pathways connecting the hypothalamus to the brainstem control centers...what are these (3)?


which of these pathways is bidirectional?

  1. Mammilotegmental tract - unidirectional
  2. Dorsal longitudinal fasciculus -unidirectional
  3. Medial forebrain bundle - bidirectional




the mammilotegmental tract goes from where to where? (structurewise)


what about the dorsal longitudinal fasciculus?


what about the Medial forebrain bundle?

  • mammillary bodies to pontine and midbrain reticular formation, and raphe nuclei.


  • from medial hypothalamus to brainstem CN’s involved in ANS, reticular formation and continues into spinal cord. 


  •  In one direction: medial hypothalamus, septum, and amygdala, to brainstem CN’s, and spinal cord.

    • in the other direction: Neurons in brainstem go to septum, prefrontal cortex, hippocampus,


Differences between ANS and SNS?

SNS: Sensory stimuli are consciously perceived.       Motor component: voluntary movement.

ANS:  Sensations generally not consciously perceived.

           Motor component: smooth and cardiac muscle.


What are the Functional Aspects of the ANS?

  • Maintains body homeostasis.
  • Sympathetic prepares and mobilizes body for emergency.
  • Parasympathetic conserves and stores energy
  • Sympathetic and parasympathetic have antagonistic actions


what effect does the Parasympathetic Division?

**remember: SLUDD**

  • Salivation
  • Lacrimation
  • Urination
  • Digestion
  • Defecation


Also: decreases heart rate, causes pupillary 

constriction and bronchioconstriction.


the sympathetic division of the ANS takes care of these   actions...

  • Pupillary dilation
  • Increases in heart rate, blood pressure, etc.
  • Dilation of airways
  • Constriction/dilation of blood vessels
  • Release of glucose from liver
  • Inhibition of GI and digestive processes


where does the Enteric Division begin?

what does it do?

  • Originates in enteric ganglia and GI tract plexuses.
  • Is involved in GI motility.


Parasympathetic includes which cranial nerves?

Sympathetic includes which cranial nerves?

Craniosacral: CN’s 3, 7, 9, 10 and cord segments S2, S3, S4


Thoracolumbar: from T1 to L2 and uses sympathetic



the sympathetic and parasympathetic systems have which, pre-ganglionic or post ganglionic? what is the difference?

What does the SIF contain?

When ACh gets released, what 2 other neurotransmitters get released as well?

both yet sympathetic has interneurons called SIF


SIF contains dopamine


VIP and NO because they are stored with ACh


what is nicotine?

what is its antagonist?

where does nicotine act?

ACh agonist


at neuromuscular junction and postganglionic neurons


what is a muscarine receptor?

what is its antagonist?

where does it act?


ACh receptor agonist 


parasympathetic effectors


what is Isoproterenol?

what is its antagonist?

beta 2 adrenergic agonist receptor



what is an alpha adrenergic agonist?

what is its antagonist?




what is a beta 1 agonist receptor?

what is its antagonist?





where do Preganglionic sympathetic fibers exit the spinal cord?

where do Preganglionic sympathetic fibers enter the sympathetic trunk?

some preganglionic sympathetic fibers synapse at the sympathetic trunk...where exactly? what happens to postganglionic fibers that exit the sympathetic trunk? 

  • via the ventral roots
  • via the white communicating rami
  • at the paravertebral ganglia
  • the postganglionic fibers join the spinal nerves via the grey rami


what is the effect of the sympathetic system on the pupil?


what is the effect of the parasympathetic system on the pupil?






What glands receive both sympathetic and parasympathetic innervation?


lacrimal, salivatory and glands


What is Horner's Syndrome?


how do you get it?

  • interruption of the oculosympathetic pathway. 
    • pathway runs from the hypothalamus, down

      through the lateral aspects of the brainstem into the lateral white matter of spinal cord, and exits via the plexuses.

  •  from hypothalamic lesion, brainstem or spinal cord lesion, or even plexus lesion, Compression of the superior cervical ganglion


what are the symptoms seen in Horner's?





Loss of ciliospinal reflex (normal reflex is dilation of pupil in response to painful stimulation of ipsilateral face, as in a pinch on the cheek)


What does opthalmoplegia mean?

damage to what will result in internal ophthalmoplegia?

what are the symptoms of ophtalmoplegia?


  • paralysis of eye muscles
  • damage to Edinger-Westphal nucleus of CN 3
  • fixed and dilated pupil, and loss of accommodation reflex (cycloplegia)


where do 2nd order neurons synapse?

anterior white commissure


what is accomodation reflex?

 Ask patient to watch finger as it moves towards their nose.  As their eyes adduct, the pupils constrict.



What is Adie's Pupil?

what causes it?

what do you call Asymmetric pupils?

What is Adie's Syndrome?

What are the symptoms for Adie's Syndrome?

  • Patient has fixed, dilated pupil.
  • Damage to ciliary ganglion or nerves. 
  • Aniscoria
  • When there is damage to ciliary ganglion as well as dorsal root (spinal) ganglion resulting

  • decreased deep tendon reflexes, anhydrosis,

    postural hypotension and unsteady heart



what is Autonomic Dysreflexia?

What is the characteristic symptom?

  • An exaggerated response of the sympathetic system following spinal cord injury at or above T6.

There is an interruption of control of ANS by higher centers.

  • profuse sweating above injury level and dry skin below.


What is Raynaud’s disease?

what is the treatment?

  • terminal arteries of the extremities have excessive sympathetic stimulation causing vasoconstriction of arterioles in fingers and toes, causing pain and reduced blood flow
  •  treated with preganglionic sympathectomy



what is another name for Familial dysautonomia?

who does Familial dysautonomia affect?

what symptoms are seen?

why does it happen?

Riley Ray syndrome

Ashkenazi Jews

  1. Abnormal sweating.
  2. Unstable blood pressure.
  3. Difficulty in feeding.
  4. Progressive sensory loss


There is loss of autonomic and sensory ganglia neurons.



what is Hirschprung's disease?

what symptoms are seen?

  • aganglionic megacolon; specifically, absence of myenteric plexus ganglions due to non-migration of neural crest cells
  • extreme dilation and hypertrophy of the colon, fecal retention


what is another name for Multiple System Atrophy (MSA)?

characteristic symptoms?

reason it happens?

Shy-Drager Syndrome

orthostatic hypotension, anhidrosis, impotence, and atonic bladder, parkinsonian symptoms (slow movement) and ataxia

CNS degeneration



what is Lambert-Eaton myasthenic syndrome?

what will it cause?

what should you look for in the case stem?

presynaptic defect in ACh release

weakness of limb muscles but not bulbar muscles.

when patient starts using muscles..muscle strength returns


what is Anaphylactic Shock Syndrome?

what is the treatment?

What is the effect of beta 1 binding?

What is the effect of beta 2 binding?

What is the effect of alpha 1 binding?

  • Severe systemic allergic reaction resulting in bronchoconstriction and systemic vasodilation
  • treat with adrenergic agonist at both beta 1 and beta 2 receptors and alpha 1 receptors
  • beta 1 binding = increase heart rate
  • beta 2 binding = bronchiole dilation
  • alpha 1 binding = vasoconstriction