Block 2 Visceromotor (Autonomic) Mechanisms-Peripheral And Central Reflex

Front 1

where are the visceral efferent neurons located?

Back 1

cranial nerves 3,7,9,10 and S2-S4 (for parasympathetic)

T1-L2 for sympathetic

Front 2

all autonomic ganglia. preganglionic axons release ______ that acts on ____receptors on postganglionic cells

Back 2

acetylcholine that acts on nicotinic receptors on postganglionic cells

Front 3

Posterganglionic parasym vs. symp

Back 3

parasympathetic: release ACh that acts on neuroeffector cells thru muscarinic receptors

sympathetic postganglionic release NE that act on neuroeffectors cells through Adrenergic receptors

Front 4

autonomic control is or is not under direct voluntary control?

Back 4

is NOT. automatic!

though you can influence visceral control by behavioral changes like stress reduction to lower BP. these changes are usually more gradual that skeletal motor response

Front 5

parasympathetic nerves and what they innervated

Back 5

craniosacral outflow

CN3=eye, iris, ciliary, lacrimal glands
CN7/CN9=Salivary Glands
CN10=Thoracic/Abdominal Viscera

Sacral Cord (S2-4)=rectum, bladder, sex!

Front 6

parasympathetic has ____preganglionic axons and ____post ganglionic axons

what NT used? type of receptor?

Back 6

LONG pre, short post. the ganglia are located within the walls of the organ!

Pre=ACh Nicotinic
Post=ACh Muscarinic (G protein coupled)

Front 7

overall function of parasympathetic

Back 7

promotes activity that restore metabolic needs for body/get rid of waste

salivation, lacrimation, urination, disgestion, defecation, HR decrease

REST AND DIGEST

Front 8

sympathic nerves and where they are located

axons of pre and post ganglionic long or short?

Back 8

T1-L2. preganglionic located in ganglia close to spinal cord (paraveretbral chain+thoracic mesenteric ganglia)

pre short
post long

Front 9

sympathetic NT? and receptors?
pre?
post-ganglionic?

Back 9

pre=ACh with Nicotinic receptors

post=Norepinephrine with Adrenergic receptor types (G protein coupled)

Adrenergic can be divided into alpha and beta subtaypes based on pharmacolgic properties

expection: sweat glands/pilomotor muscles use ACh

Front 10

stuff that happens in flight or fight response. name 6 things

Back 10

increased blood sugar
increase HR/maintain BP
Direct blood flow to needed area (restricting to smooth muscle, dilating arterioles to skeletal muscle)
dilating bronchioles
piloerection

Front 11

usually individual components of the system are activated as a whole instead of individual stimuli. True or false?

Back 11

FALSE. usually activated by individual stimuli without activation of whole system

ex) suddenly standing from a reclining position activates sympathetics to JUST the heart and vasculature to maintain blood flow to the brain-doesn't affect the entire system

Front 12

how does the adrenal medulla affect sympathetic activity?

Back 12

the adrenal medulla is innervated by preganglionic symp neurons, but no post.

secrete catecholamins into the dense capillary bed of medulla

blood carries NT to ALL symp adrenergic receptor sites in all tissues

only activated during stress=prolongs fight or flight

Front 13

what percent of catecholamines released from the adrenal medulla is NE and E?

Back 13

70-80% is epinephrine
20-30% is norepinephrine

Front 14

nicotinic receptors have what kind of channels?

why are they called "nicotinic"?

what blocks them?

Back 14

ionotropic cation channels

called nicotinic because nicotine acts as an agonist at these receptors

blocked by hexamethonium

Front 15

muscarinic receptors use what kind of mechanism?

why are they called muscarinic?

antagonist?

excitatory or inhibitory?

Back 15

metabotropic, G-protein coupled mechanism

activated by muscarine (from shrooms!)

antagonist=atropine

could be either one! all depends on which neuroeffector site!

ex) excites GI tract smooth muscle but inhibits cardiac pacemaker cells

Front 16

nicotinic and muscarinic are what type of receptors?

Back 16

cholinergic

Front 17

adrenergic receptor types: respond thru what mechanism? excitatory or inhibitory?

strongest alpha agonist is?
alpha antagonist?
beta agonist?
beta antagonist?

Back 17

g-protein coupled mechanism. excitatory at some, inhibitory at others

alpha agonist=norepinephrine
alpha antagonist=phenoxybenzamine
beta agonist=isopreteranol
beta antagonist=propranolol

Front 18

the brainstem provides organizing centers for ________outflow

Back 18

parasympathetic

Front 19

bladder emptying is promoted by _____activity while _____activity promotes bladder relaxation

Back 19

emptying promoted by parasymp
bladder relaxing promoted by symp

Front 20

explain how the bladder talks to to the nervous system. bladder emptying reflex.

how do high motor centers affect bladder emptying? what is this called?

Back 20

stretch receptors in wall of bladder enter sacral cord and excite parasymp preganglionic motor neurons

these neurons excite the bladder wall muscle and inhibit the internal bladder sphincter

high motor centers excite alpha motor neurons in sacral cord. their axons travel by the pudendal nerve to excite external bladder sphincter (striated muscle) to stop urine outflow="conscious suppression of bladder emptying"

Front 21

3 sources of efferent and afferent signal transmission of the bladder. name the nerve/nerve origins

Back 21

somatic innervation (onuf's nucleus at S2,3,4 via pudendal nerve)

sympathetic innvervation (T11-L2 via hypogastric nerve)

parasympathetic innervation (S2,3,4 via pelvic nerve)

Front 22

what neurons cause bladder filling? phasic or tonic?

Back 22

somatic neurons-contract external urethral sphincter

sympathetic-contract internal urethral sphincter+relax detrusor mulsce that expels urine from the bladder

TONIC ACTIVITY

Front 23

what innervations cause bladder emptying?

Back 23

all 3 innervations!

somatic-inhibited=relax external sphinc
sympath-inhibited=relax internal sphinc
parasym-stimulated=stimulate detrusor muscle contraction

Front 24

blood pressure control. which areas are pressor effects and which are depressor effect?

Back 24

the lateral and pontine areas=pressor

medial and medullary areas=depressor effect

Front 25

sensory input for BP control comes from baroreceptors of the carotid sinus and aortic arch by way of which cerebral nerve?

where do they synpase?

Back 25

CN 9 and CN10

synapse in the NTS (nucleus of solitary tract)

*further integration by cardiovasc regulating neurons of medullary reicular formation

Front 26

When BP increases above it's set point, what happens?

what else does NTS do?

Back 26

Baroreceptor freq increases
NTS neurons excited
Parasymp pregang are excited=decrease HR

NTS also excited interneurons in cVLM, which inhibit rVLM (which are normally excitatory symp pregang)

Front 27

what is the interaction btw NTS, cVLM, and rVLM?

Back 27

NTS activity excites cVLM, which inhibits rVLM (which is responsible for excitatory activity of heart)

Front 28

when BP decrease below it's setpoint, what happens?

Back 28

baroreceptors freq decreases->NTS neuron less excited->parasym outflow decreased+cVLM not excited->rVLM is turned on=increase in symp tone->increased HR

Front 29

what are the 2 sets of smooth muscle in the iris that regulate diameter of the pupil?

Back 29

the radial-dilates pupil (excited by sympath)

the circular-constricts pupil (excited by parasympath) parachute is circular

Front 30

pupillary light reflex:

diffuse light activates _________ganglion cells which synapse in ______nucleus.

these neurons project bilaterally to excite ________ neurons of edinger westfall nucleus.

this _____outflow results in_______

Back 30

activates w-type retinal ganglion cells which synapse in the pretectal nucleus


pretectal neurons project bilaterally to excite parasymp neurons of edinger westfall nucleus

this parasympathetic outflow results in bilateral pupil constriction

Front 31

pupil dilation:

during periods of excitement or threat, symp acitivity increases in ______ of the spinal cord

symp outflow travels thru _______ and _______ to excite _____muscle of the _____

this results in pupil dilation

Back 31

T1-T3

travels thru the cervical symp trunk and superior cervical ganglion to excite radial muscle of the iris

results in pupil dilation

Front 32

horner's syndrome.

what causes it?
symptoms?

where can the injury occur?

Back 32

results from injury to the sympathetic supply to the head

symptoms:
miosis (pupil contriction cuz no symp to parasymp input)
ptosis: drooping of eyelid
enophthalmos (sinking of the eye in it's socket)
hypohydrosis (lack of facial sweating on side of injury)

1) hypothal->medulla fibers (in reticular formation)
2)symp pregang neurons in upper thoracic cord
3)tumors in upper thoracic cavity affecting superior cerv gang
4)compression of symp nerves in carotid plexus

Front 33

what is pheochromocytoma?

symptoms?

Back 33

tumor of the adrenal gland=tumor secretes excess epinephrine and norepinephrine

symptoms: severe HTN, Tachycardia

Dilated Pupils

Headache, perspiration, pale cold extremities

Front 34

Shy-Drager Syndrome

Back 34

results from loss of sympath neurons in intermediolateral spinal cord

symptoms?
failure to adjuct BP and HR in response to stress
orthostatic hypotension
hypohydrosis, dry mouth, impaired temp regulation
excess response to inject Epi.