8 Flashcards
what is the sympathetic action in the head
pupil dilation
blushing
reduction in salivation
where are pregnglionic sympathetic visceral motor neurones
intermedialateral part of the grey mater.
in the thing that looks like a deer.
it goes from preganag to white Ramus to postgang to smooth and muscle and such.
are pregnglionic sympathetic visceral motor neurones VENTRLA OR DORSLA
VENRTAL
whats a sympathetic chain made up of
25 ganglia and the sympathetic trunk
where does the sympathetic chain run from to
cervical spinal cord to L2
what two key characteristics are shown by sympathetic trunk
convergence: many diff pregang can synapse in one single postgang
divergence: different pregang will synapse at diff vertebrae levels
whats special about the rostral apart of the sympathetic chain
3 cervical ganglia are not connected to cervical spinal cord but rather to thoracic spinal cord from T1 down.
they are called the superior cervivalg ganglion, middle and inferior.
they innervate face to make blushing, NO mucus secretions and pupil dilation
where do superior middle and inferior preganglionic neurones arise form
thoracic spinal cord from T1 down.
in tear so of number of neurones involved whats the difference between ANS and SNS
somatic has 1 to neuromuscular junction
ANS has two pregang and posting
whats the structure of pregang and postgang
myelinated with A and B axons
post gang have unmelinated with type C axons.
think of a shirt you wear 3/4
how do sympathetic postganglionic neurones act on muscles
release adrenaline to alpha 1 receptor .
how does sympathetic innervation below the diaphragm occur
via
celiac plexus to liver stomach start of SI
inferior mesenteric plexus rest of gut
hypogastric plexus to bladder and reproductive organs
whats the greater splanchnic nerve
its the preganglionic neurone to the celiac plexus
whats the lesser splanchnic nerve
its the preganglionic neurone to the inferior mesenteric plexus
T10
whats the sacral splanchnic nerve
its the preganglionic neurone to the hypogastricplexus
L3
why is the adrenal gland imp in the symatheitc NS
its a postgnaglion neurone that never grew an axon.
releases adrenaline in blood stream. by chromatin cells int he medulla.
receives input from pregang.
do all postganglionice cells release Adrenaline
all except sweat gland.s
they release Ach which activates No release in blood vessels hat supply the glands. which increases bloodf low into the glands to be secreted as sweat
what drugs block sympathetic effects and whats the main risk with them
beta blockers
prazosin
hypotension and death
are all vascular beds prone to vascular tone control
tout sauf brain and heart
what happens during exercise
local chemical facts like pH cause local vasodilation by SNS copes by causing vasoconstriction everywhere else Sauf exercising muscle.
where is alpha 1 receptor found
antagonist
vascular SM
antagnosi t is prazosin. reduces BP
where is alpha 2 receptor found
antagonist
pregang sympathetic nervous terminals
clonidine reduces BP
where is beta 1 receptor found
antagonist
heart and kidneys
increase force of contraction of myocardium
antagnist reduce HR in stressed or HT people bisoprolol
where is beta 2 receptor found
bronchi relax muscle
agonists causes relaxation in asthmatics salbutamol (short actin)
where is beta 3 receptor found
increase lipolysis and gluconeogenesis and adipose tissue.
what happens during exercise
B1 increases HR
B2 relax bronchi
B3 increases lipolysis
what happens during haemorrhage injury
vasoconstriction
alpha receptors increase clotting speed.
