Lecture 5 Flashcards
The autonomic nervous system controls everything except what?
Skeletal muscle
Where do the pre-synaptic fibers leave the spine in the sympathetic divisors?
At the level of the thoracic vertebrae and upper lumbar
Where do sympathetic division synapse?
In the paravertebral chain
In the sympathetic, is pre or post longer?
Post is longer and pre is shorter
What does the sympathetic innervates?
Innervates walls of organs, glands and smooth muscle
What is sympathetic mediated through?
Epi and norepinephrine
Pre synaptic fibers leave the spine at what level for the parasympathetic?
Cranial nerves 3,7,9,10 and sacrum
Where does parasympathetic synapse?
In or near the target organ
In parasympathetic, does pre or post have longer?
Pre is short and post is long
What is the parasympathetic mediated by?
Acetylcholine
What NT is present on pre and posy synaptic for PNS?
Acetylcholine!!
- nicotinic receptor on post
- muscarinic on target
SNS has what NT for pre always?
Acetylcholine
What NT is USUALLY for post on SNS?
Norepinephrine
What NT is for post synaptic for sweat glands?
Acetylcholine
What NT is for post for SNS on kidneys?
Dopamine
What does the adrenal medulla function as for the SNS?
A post-synaptic neuron
The autonomic nervous system ganglia forms __________ where NTs are stored
Varicosities
NT are stored in vesicles with _____________ and released onto smooth muscle
Neuromodulators
Both divisions of the autonomic NS have what kind of receptors on their pre synaptic nerves?
Nicotinic
The parasympathetic has what kind of receptors on target organs?
Muscarinic (M2 and M3)
The SNS has what kind of receptors on target organs?
Adrenergic receptors (alpha and beta 1 and 2)
Alpha 2 adrenergic receptor regulates what? It modifies the SNS response by what? What is the mechanism?
- regulates release of epi and norepinephrine
- modulates by a negative feedback loop
- it inhibits cAMP which inactivates calcium so NT are not released
Maximal effect of dual innervation requires….
-full stimulation by one and full stop of stimulation of the other
In most organs, which division predominates the resting tone>
PNS
What part of the body is not under tonic PNS control?
The freaking heart
The dilator muscle is innervates by what? Constrictor?
Dilator: SNS
Constrictor: PNS
Is accommodation autonomic mediated?
Oh hell yea
The detruser muscle of the bladder is controlled by which division when it is relaxed?
Relaxed-sym
Contracted-PNS
The internal sphincter of the bladder is controlled by what division?
Relaxed: PNS
Contracted:SYM
Which division could we still live without if he had to?
Sympathetic
What do afforestation sensory nerves do?
Carry information to appropriate region of the brain or hypothalamus
What do efferent nerves do?
Carry responses to the target organ
What nerve usually acts as the efferent nerve in the PNS?
Vagus
What do baroreceptors do?
Sense a drop in blood pressure
The SNS efferent response is carried along what nerve?
Thoracic nerves
What is the mechanism for normalizing blood pressure?
Reduce PNS on the SA node and increase heart rate
Increase SNS on the SA node and increase heart rate
Increase adrenal release and increase heart rate
