atomic nervous system Flashcards
ANS Sub-division of the
peripheral nervous system
is it ubder consius control
NOT under conscious control
automotic
what does it control
Controls non-skeletal peripheral function:
examples
Cardiac muscle (heart)
Smooth muscle
Internal organs
Skin
somatic sensory responds to what stimuli
external
Visceral sensory
responds to what stimuli
internal
how are the info carried to the brain
via cranial/spinal nerves (PNS)
lastly
relayed to the brain
what is teh sensory division known as
afferent
and the motor
efferent
what are the 2 branches of the motor division
Somatic motor
Visceral motor
which path do the para/sympthatetic pathways originate from
Visceral motor
what arises from the efferent divsion
somatic and automic nervous system
what is the automic nervsous system branches
sympathetic and para
function of Parasympathetic
“Rest & Digest”
Routine maintenance
Sympathetic
function
“Fight & Flight”
Mobilisation & increased
metabolism
can they innervate/stimulate the same tissue
yes
what affect
opposing/antagonistic
pns and sns affect on STOMACH
Parasympathetic
higher motility & secretions of digesting enzmye
opposite for s
Liver pns and sns
more bile release in pns
sns: more glucose
what is the other exception to opposing rule
SNS controls blood vessel tone – both constriction and dilation
what do baroreceptors respond to
blood pressure
if bp is high
the baroreceptors firing rate is high
how is the sypmathtic nervous system dominant ove rpns
e.g. baroreceptor firing rate drop
stimulus to inhibit the sympathetic nervous system drops
so sns switches on
what is the system called
disinhibition
In psychology, disinhibition is a lack of restraint manifested in
Visceral motor nuclei originate in
the hypothalamus.
where do the VMN project to next
brainstem/spinal cord
what happens there
they synapse with automin nuerons §
In general, autonomic neurons consist of how many nuerons
two neurons
what are they
a pre-ganglionic and a post-ganglionic neuron
what is a ganglion
nerve cell cluster or group of nerve cell bodies
describe the ganglions in PNS
Long pre-ganglionic fibres
Ganglions close to (or embedded within) effector tissues.
so a Short post-ganglionic fibres
and SNS
Short pre-ganglionic fibres
Ganglions close to spinal cord.
Long post-ganglionic fibres
what is the sympathetic trunks
lots of nerves running parralell to the spinal cord
what doe sit cause
mass activation
what is the one exception to two neuron arrangement in ANS
Sympathetic innervation of the adrenal gland
what is inbetween the pre and post ganglionic fibres
the ganglion
how does it differ to the 2 nueron rule
only has one nerve stimulating the adrenal gland
what do both pre and post ganglionic fibres release at their synapse at the PNS
Ach = Acetylcholine
w a the sypmathetic pre and post ganglionic fibres
pre releases Ach = Acetylcholine
post releases NA = Noradrenaline
why doesnt the Sympathetic NS when activating the adrenal gland have a post gf
Adrenal gland secretes a hormone
NOT a neurotransmitter
Adrenaline (and some noradrenaline)
Secreted into bloodstream
NOT synapse
what part of the adrena gland relasaes adrenaline
medulla
how many sympathetic nuerons are there in the lung
There are NO sympathetic neurons innervating the lung tissue
only PN
so how does dilation of the
broncho take place
SNS stimulate teh release of adrenaline from adrenal medulla
a will pass to the lung via blood
diffuse into the long
causing broncho dilation
when smelling food what nervous system is activated
PNS tells stomach to strat contratcing and relaseaing digestion enzymes
reflex response
what is the guts own nervous system called
enteric nervous system
nervous control in gut that can occur independenlty of the gut
what is the sensory information recived by your bladder
pressure
what muscle does the PNS control
Detrusor muscle
function
control the bladder
what does the SNS control
Internal sphincter
moderate pressure is controlled by what
SNS the Internal sphincter
is closed/contracted
what happens as it reaches a certain point
para switched on and s switched off
causing
Detrusor muscle
Contracts
Internal sphincter
Relaxes
Q: What type of receptor would you want at autonomic ganglia?
Nicotinic
acetylcholine
receptor
Ion channel receptor
what is special aboutIon channel receptor
FAST response (msecs)Mediate all fast excitatory and inhibitory transmission
function of Nicotinic acetylcholine (nACh) receptors
mediate the responses to acetylcholine released from preganglionic fibres at all autonomic ganglia.
what do they do at sympathetic nerves to the adrenal gland
mediate the response to acetylcholine released by sympathetic nerves innervating the adrenal medulla
what are Muscarinic Ach receptor
respond to Ach release from post-ganglionic PNS fibres.
Adrenergic receptors
respond to NA release from post-ganglionic SNS fibres or adrenaline via blood.
what type of receptors are both of them
g coupled protien receptors
how to make acetly choline
Choline + acetyl CoA
what enzyme needed
choline acetyl transferase
how is Ach degraded and where
synapse
acetylcholinesterase
what happens to the choline
taken up into preST or glial by choline uptake protien
What happens if you block acetylcholinesterase?
accumalation of ach
more powerful affect
how is noradrelanine made
step 1
Tyrosine converted to DOPA
by what enxyme
by tyrosine hydroxylase
next step
DOPA converted to dopamine
by what enzyme
DOPA decarboxlase
what is packaged in vesicle
Dopamine
dopamine β hydroxylase
what is the product
Noradrenaline
what receptor is activated when Noradrenaline is exocytosed
adrenergic
how is it removed from synapse
synapse via uptake into pre-synaptic terminal or glial cell;
Can be metabolised in the synapse prior to uptake
what protien uptakes it in PreST
uptake 1 protien
and in glial
uptake 2
How would this change for adrenaline release from adrenal gland?
same stuff to convert to noradrelaline
but its then coverted to phenylethanol
where
cytoplasm
by what enzyme
methyl trasnferase
is the exocytosis different
no
same stuff like action potential casuing ca 2+ influx
next
- Adrenaline diffuses into capillary and is transported to tissues in the blood
Autonomic sensory (afferent) information relayed to
hypothalamus
where does ANS neurons originate
in brainstem/spinal cord
