ANS Sympathetic Flashcards
what is the overall function of sympathetic NS
mobilize body for action
where do preganglionic neurons arise from
T1-L3
the adrenal medulla is a specialized
sympathetic ganglia
describe pre and post ganglia length for SNS
short preganglionic
long postganglionic
describe the pre and post ganglionic cells and their myelination
pre are myelinated
post are not myelinated
adrenalla medulla contains
modified sympathetic postganglionic neurons (adrenal chromaffin cells)
what are adrenal chromaffin cells
modified sympathetic postganglionic neurons
draw out the exceptions to SNS
pg 4
look at list of sympathetic receptors, find similarities, organize, understand, know
pg 6 & 7
what is Hyperhidrosis
excessive and unpredictable sweating
how does botox prevent swelling
it blocks release of Ach, so person doesn’t sweat
chromaffin cells are modified
sympathetic post-ganglion cells
describe the length of pre and post ganglia in adrenal medulla
both are short
what is the cell in adrenal medulla important for SNS
chromaffin cells
what is released from pre and “post” ganglia in adrenal medulla
pre: Ach
post: EPI & NE
what is ratio of EPI and NE released from adrenal medulla
80% EPI
20% NE
where do EPI and NE bind
alpha and beta receptors
the adrenal medulla reinforces
the actions of sympathetic NS
is adrenal medulla always activated as part of SNS?
no
activation of adrenal medulla is associated with
stress
what kind of receptor is α adrenergic receptor
G protein coupled
where are α adrenergic receptors found
smooth muscles & glands
what is a typical α 1 agonist
phenylephrine
“Phenyl a friend”
phenylephrine is used primarily for what three things
decongestant
pupillary dilator
vasopressor
explain how phenylephrine can be used as decongestant
vasoconstriction of nasal sinusoidal vessels to decrease nasal blood flow which will then decrease musous
how is phenylephrine used as pupillary dilator
eye drops to enhance visualization of the retina by contracting the radial muscle to dilate the pupil.
how is phenylephrine used as vasopressor
contracts peripheral arterioles to increase blood pressure without significant effects on heart rate or contractility.
what is an antagonist against α 1 and α 2
phentolamine
“Phen told on me”
What is phentolamine used primarily for
vasodilator
target cells can respond to the same neurotransmitter differently depending on
the type of receptor they have
NE stands for
norepinephrine
NE activation of α 1 receptors on vascular smooth muscle cause
constriction
NE activation of ß2 receptors in detrusor muscle cause
relaxation
where are α2 receptors likely to be found
adipose tissue
pancreas
smooth muscle of blood vessel
what is the result of α2 receptors on adipose tissue
inhibition of lipolysis
what is the result of α2 receptors on pancreas
inhibition of insulin release
what is the result of α2 receptors on smooth muscle of blood vessel
contraction
Look at chart on pg 35 & 36
find patterns, understand
ßadrenergic receptors are all
G protein coupled receptors
where are ß adrenergic receptors most likely to be found
cardiac muscle, smooth muscle, glands
what is agonist for ß1 & ß2
isoproterenol
what is isoproterenol used for
treatment of
bradycardia, heart block and
rarely for asthma.
what affects does isoproterenol have on the heart
inotropic & chronotropic effects
ionotropic & chronotropic effects mean that isoproterenol will
elevate systolic BP