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Flashcards in Autonomic Response to Exercise Deck (61):

what 3 things does the ANS influence

smooth muscle, glands, and the heart


what does the ANS regulate

1. organs to maintain homeostasis
2. stress response
3. reproduction
4. thermoregulation
5. enteric system


sympathetic pathways come out of what region in the spinal cord

- thoracic and lumbar region
(T1- L2)


in the sympathetic NS the preganglionic neuron releases ____ and the post ganglionic neuron releases____

- ACh
- nor epi, epi and a trace of DA


in the parasympathetic NS, _________ receptors for _____ are at the post ganglionic neuron and release___ at the target organ

-nicotinic cholinergic receptor
- ACh


the preganglionic neuron is longer in ?

parasympathetic division


what are the 2 main NT

ACh and norepi


each NT may ? (2)
--> the response depends on?

1. stimulate activity in some tissues
2. inhibit activity in some tissues
--> specialization of the tissue (effector organ) cells: (can have many different types of receptors)


2 types of cholinergic receptors

nicotinic and muscarinic


what happens at the nicotinic receptor? and where is it found?

- binding of nicotine mimics action of Ach
- neuromuscular junction, postganglionic parasympathetic and sympathetic


what are muscarinic receptors activated by?
- where are they found
- how many subtypes?

- activated by mushroom poison, muscarine
- found on the effector cell membranes (smooth muscle and cardiac muscle glands) (only parasympathetic junction b/w post ganglionic neuron and organ it innervates)
- 5


what do adrenergic receptors bind?
what are the 2 subclasses?
where are these receptors found?

- epi and norepi
- alpha and beta
- only on target organ


what are the 5 subclasses of adrenergic receptors

- alpha 1
- alpha 2
- beta 1
- beta 2
- beta 3


-what organs have alpha 1 receptors?
- what does this have a greater affinity for?
- what does it activate or inhibit
- excitatory or inhibitory effect?

- most vascular smooth muscle, pupils
- norepi
- activates IP3
- excitatory


-what organs have alpha 2 receptors?
- what does this have a greater affinity for?
- what does it activate
- excitatory or inhibitory effect?

- CNS, platelets, adrenergic nerve terminals (autoreceptors, some vascular smooth muscle, adipose tissue
- norepi
- inhibits cAMP
- excitatory


-what organs have beta 1 receptors?
- what does this have a greater affinity for?
- what does it activate
- excitatory or inhibitory effect?

- CNS. cardiac muscle, kidney
- same for epi and norepi
- activates cAMP
- excitatory


-what organs have beta 2 receptors?
- what does this have a greater affinity for?
- what does it activate
- excitatory or inhibitory effect?

- some blood vessels, respiratory tract, uterus
- epi
- activates cAMP
- inhibitory


-what organs have beta 3 receptors?
- what does this have a greater affinity for?
- what does it activate
- excitatory or inhibitory effect?

- adipose tissue
- same for norepi and epi
- activates cAMP
- excitatory


what adrenergic receptors do we have very few of?

beta 3


this adrenergic receptor will cause vasodilation to smooth muscles and constriction to other organs during exercise

alpha 1


what is the advantage of dual innervation

when we have an increase in parasympathetic activity it is usually paired with a decrease in sympathetic and vice versa
'an antagonistic system'


3 exceptions to dual innervation

1. innervated blood vessels: only sympathetic (the only blood vessels with dual innervation are those supplying the penis and clitoris where parasympathetic causes vasodilation)
2. sweat glands: parasympathetic only
3. salivary glands: innervated by both systems but both systems stimulate salivary secretions


a unique endocrine component of the sympathetic system - a modified sympathetic ganglion

the adrenal medulla


the adrenal medulla doesnt give rise to ?
- stimulation of the preganglionic fibers causes the release of hormones in to the blood? (what ones and what %?)

- postganglionic fibers
- 20% norepi
- 80% epi
- trace of Dopamine


whenever we have a sympathetic response we also have a ______ response to help _____ the response

- endocrine
- amplify


4 functions of the parasympathetic activity

1. quiet relaxed state
2. active in rest and digest or breed and feed
3. increases GI tract activities
4. decreases HR and BP


6 functions of the sympathetic activity

1. fight or flight
2. prepares fro emergency, stress, exercise
3. increase HR and BP
4. mobilizes energy stores
5. dilates pupils
6. decreases GI tract and urinary functions


tonic activity at rest (both branches active)
- at rest though what system dominates

(we ride the break)


what gives us a tool for measurement of the health of the autonomic system
- looks at the interplay between SNS and PNS

heart rate variability


does HRV cause states? disease etc

- but long term dominance of sympathetic division is associated with problems


HRV, ore than HR or BP may be more indicative of ?

high stress situations


low HRV has been associated with ? (6)

1. asthma
2, diabetic neuropathy (body is in a stressed state= imbalance b/s PNS and SNS)
3. congestive heart failure
4. concussion (body trying to stay in homeostasis)
5. sudden cardiac death
6. predictive of death after heart attack (independent of other risk factors) --> increased risk of cardiac disease


differences in HRV but not ____ were found in surgeons performing new procedure compared to a well practiced one



factors influencing HRV

- sex (males and post menopausal women)
- age HRV is lower in the old and very young (may be masked by fitness and sex)
- medical condition
- levels of fitness: high cholesterol, high fitness = low HRV


what does the time domain measure?

- simple measure of HRV
- measure NN intervals of instantaneous HR
- usually over long periods of time (24hours)


what does the frequency domain measure?

provides info on how power (variance) distributes as a function of freq
- can use short term recordings
- most often FFT (simple algorithm) to determine HF, LF and VLF
- can be measured in absolute values (m2) or normalized units

--> looking at what is the variance in HR we see over
--> snap shot of what is happening


not fully understood but it it thought to be affected by temperature regulation and humeral system

VLF (ms^2)


what is HF?
what is LF?
--> units

- parasympathetic activity of the ANS and respiratory rhythm
- sensitive to parasympathetic nerve activity
--> n.u (normalized units)


what is LF/HF

reflects the balance which exist between the 2 systems


how do you calculate LF and HF powers in normalized units



what is the LF/HF ratio in healthy adults
- what ratio is associated with predominated vagal tone
- what ratio is indicator of dominating sympathetic activity

- between 1.5-2.0 or 1.5 +/1 2
- < 1.5
- > 2


greater HRV is caused by an _____ in LF and a _____ in HF

- rise
- decrease
--> this doesnt seem right to me


the ____ domain is under parasympathetic regulation from the ______ activity and represents heart beat oscillations that occur due to _______ _______

- HF
- vagal
- respiratory frequency


the ___ domain is under joint control from the sympathetic and parasympathetic regulations, with sympathetic control dominating during time of _____

- LF
- stress


what does displaying the LF and HF components in n.u do?

highlights the control and balance behaviour of the sympathetic and parasympathetic nervous system


what is the normal value for total power

3466+/- 1018


what is total power a sum of



what is the normal value for LF

54+/- 4


what is the normal value for HF

29 +/- 3


what happens to HRV during exercise and why ?

it reduces because we have increased sympathetic dominance


when did have fire fighters have a decrease in HRV?
- what may contributed to this?

- up to 4-5 hours following night time call
- on the first 2 nights off following a night shift
--> decrease due to heat stress
--> decrease by psychological stress


ppl with DS had _______ dominance during and after exercise



he elevated LF in ppl with DS is indicative of?

sympathetic dominance throughout all testing conditions


in ppl with DS, LF did not return to pre exercise values during the recovery phase of the test, 3 reasons why?

1. PNS is not appropriately acting on the SA node
2. some from of autonomic dysfunction is occurring
3. autonomic dysfunction is due to abnormality in the frontal lobe of brain


the LF/HF ratio was much higher than the normal population (in ppl with DS) what does this suggest?

even at rest they have sympathetic dominance --> increased risk of associated disease states


what do concussions result in ? (4)

- altered heart rate variability
- decreased baroreflex sensitivity
- decreased cellular metabolism
- decreased cerebral blood flow


post concussion there is disruption in neuroautonomic cardiovascular regulation, which is?

the coupling of the autonomic nervous system and cardiovascular system
(aka uncoupling happens)


do caffeine and sugar impact HRV ?

not sugar but caffiene causes increased sympathetic drive


what do spinal cord lesions have to do with HRV

depending on the height of the lesion there could be greater susceptibility to certain things
--> sympathetic innervation comes out of the thoracic region


can HRV be used to prescribe training ?



how would aerobic training influence HRV?

idk (see last slide study)