ANS
Homeostasis
• Homeostasis: maintaing an optimal internal environment and cope with
external signals/challenges
• All of the organs (spec. heart, lungs, GI, kidneys) are connected by blood, so
they can transport nutrients, hormones, etc. from one tissue to another
Essentials of life
• GI is important for digesting food/ getting the right amount
of nutrients from the food: nutrients intake and
aborbtion of water will increase
• Kideney and GI release waste and water
• Lungs are important for respiration
• Heart is important for pumping blood to all the organs
• They can all communicate to each other using hormones
(produced by a variaty of organs)- secreted into the bloodstream and travel to
all the other tissues give a signal to that specific tissue to change/increase/
decrease its fuction
Functions of blood (70 ml/kg)
1. Transportation: O2/CO2 (make sure all the organs can absorb the right amount
of oxygen and can excrete CO2), nutrients (for energy
production), hormones
2. Regulation: pH, temperature, body fluids (the blood can absorb some of it so the
organs dont have too much of it)
3. Protection: clot formation, immune system (it can transport the immune cells
to where they have to go)
Sufficient for homeostasis
• The blood has a very important role in connecting all the organ systems in
order to maintain the right homeostasis. But is this sufficient for homeostasis?
• Yes bc the blood can keep the inside environment stable
• No bc it cant cope with external signals
Sufficient for homeostasis≠ life
Tuning of communication
• The ANS is like a control center of our body, it receives
the signals from the rest of the body and form the outside,
and can send signals to the organ to change their function.
• It's essential. Without it, life would not be possible bc the
signaling thing would have to be done by the CNS which
ofc is less practical and would take longer.
,Comparison sympathetic / parasympathetic NS
Nomenclature of the Nervous System
• The nervous system is the main organ
system that sends signals from the
brain to the other parts of the body to
tune their function
• PNS is the nerves going form the CNS to
the rest of the body. CNS and PNS is the
anatomical difference.
• The brain is the main control center of
the body: it tells the organ to work in a
different way, to cope external signals, and to make sure to keep the
physiological effects
• The NS can regulate the body functions that are both voluntary and
involuntary (breathing, body temperature, digestion, blood pressure, heart
rate, etc.)
• SNS and ANS is the functional difference.
• Somatic is voluntary movements of the muscle (walk, run, etc.)
• Autonomic is responsible for regulationg of involuntary processes. Often
recalled as the vegetative nervous system.
• (ortho)sympathetic nervous system - fight or flight.
Prepares for action/stressful situations. Increases pressure and heart rate.
• Parasympathetic nervuos system- rest and digest.
Makes sure the blood pressure and heart rate come back to normal levels,
makes sure the food is digested well.
• They are different but work well together.
• The lines show how the nerves get to the
different organs and how they get back to the
CNS. It shows how the nerves innervate
• The parasympathetic nerves enter the CNS in
a neural cervicle ganglis or in a sacral
segments of the spinal chord (high in the neck
or low in the back). Bulbo (III, VII, IX, X) -
Sacral Ganglia in/on target organ
While sympathetic are more in the middle so
more in the thorax and lumbar sections.
Thoraco - Lumbar Ganglia in paravertebral
chain
It all has to do with what organs they
innervate.
• The parasympathetic is the anabolic system, it calms down the body (the rest
we take after eating is also part of this- to digest better the food)
Sympathetic (fighr or flight) is a catabolic system (burns down nutrients to
produce ATP- you need energy); so it prepares the body for action.
• There is also a difference in the neurotransmitter used to communicate through
the signals:
• Parasympathetic uses Acetylcholine
• Sympathetic uses noradrenaline/ norepinephrine. If adrenaline is released, the
body gets ready for action.
, • The system make use of long neurons:
• Parasympathetic has a long pre-synaptic neuron getting to the small circles in
the image (which represent a ganglion- cluster of nerve cells).
It has long neurons before getting to the ganglion. The ganglia are closely
located to the organs.
Long pre-synaptic neuron → ganglion (synapse) → second neuron (shorter)
to the organ system
• Sympathetic uses a chain of ganglia: long vertical chain of all clausters of
nerve cells getting together where they release neurotransmitters and
transmit signals from CNS to the PNS.
It has short pre-synaptic neurons and long post-synaptiuc neurons.
Pharmacology (neurotransmitters and receptors)
Neurotransmitters nervous system
• The white matter is the axons going down the
spinal chord (and then into the periphery).
• The somatic neurons move from CNS to a
muscle, where they release a neurotrasmitter
to make sure the muscle contracts
• The parasympathetic neuron innervates many
organs. There is a long pre-synaptic neuron,
which then meets a ganglion (a synapse happens),
the pre-synaptic neuron releases a signal that
activates the post-synaptic neuron, which then moves to the organ systems to
transmit the signal to induce an effect.
• 1st sympathetic neuron: usual structre, goes to many tissues
• 2nd: same as the 1st but uses a different neurotransmitter. If you sweat, it's
regulated by the cholinergic system(parasympathetic neurotransmitter)
• Adrenal medulla (produces noradrenaline and adrenaline):
sympathetic neurons that make use of parasympathetic neurotrasmitters.
Regulated by Ach
• All sympathetic pre-synaptic neurons use Ach and for the post it depends if it’s
somatic, parasympathetic, or sympathetic
• We make use of 2 types of neurotransmitters (acetylcholine or noradrenaline):
2 different systems
Cholinergic system: uses actelycholine
• Contains a choline group (can also
be absorbed by group) put with an
acetyl group.
• It mimicks quite well the effect of 2
exogenous compounds: nicotine
(smoke) and muscarine
(mushrooms).
• Achetylcholine can activate 2
nicotinic receptors (Nm and Nn)
and 3 muscarinic receptors (M1,
M2, M3)
there are 5 but the 4 and 5 are not so known in the sense of what processes are
regulated by the receptors
Homeostasis
• Homeostasis: maintaing an optimal internal environment and cope with
external signals/challenges
• All of the organs (spec. heart, lungs, GI, kidneys) are connected by blood, so
they can transport nutrients, hormones, etc. from one tissue to another
Essentials of life
• GI is important for digesting food/ getting the right amount
of nutrients from the food: nutrients intake and
aborbtion of water will increase
• Kideney and GI release waste and water
• Lungs are important for respiration
• Heart is important for pumping blood to all the organs
• They can all communicate to each other using hormones
(produced by a variaty of organs)- secreted into the bloodstream and travel to
all the other tissues give a signal to that specific tissue to change/increase/
decrease its fuction
Functions of blood (70 ml/kg)
1. Transportation: O2/CO2 (make sure all the organs can absorb the right amount
of oxygen and can excrete CO2), nutrients (for energy
production), hormones
2. Regulation: pH, temperature, body fluids (the blood can absorb some of it so the
organs dont have too much of it)
3. Protection: clot formation, immune system (it can transport the immune cells
to where they have to go)
Sufficient for homeostasis
• The blood has a very important role in connecting all the organ systems in
order to maintain the right homeostasis. But is this sufficient for homeostasis?
• Yes bc the blood can keep the inside environment stable
• No bc it cant cope with external signals
Sufficient for homeostasis≠ life
Tuning of communication
• The ANS is like a control center of our body, it receives
the signals from the rest of the body and form the outside,
and can send signals to the organ to change their function.
• It's essential. Without it, life would not be possible bc the
signaling thing would have to be done by the CNS which
ofc is less practical and would take longer.
,Comparison sympathetic / parasympathetic NS
Nomenclature of the Nervous System
• The nervous system is the main organ
system that sends signals from the
brain to the other parts of the body to
tune their function
• PNS is the nerves going form the CNS to
the rest of the body. CNS and PNS is the
anatomical difference.
• The brain is the main control center of
the body: it tells the organ to work in a
different way, to cope external signals, and to make sure to keep the
physiological effects
• The NS can regulate the body functions that are both voluntary and
involuntary (breathing, body temperature, digestion, blood pressure, heart
rate, etc.)
• SNS and ANS is the functional difference.
• Somatic is voluntary movements of the muscle (walk, run, etc.)
• Autonomic is responsible for regulationg of involuntary processes. Often
recalled as the vegetative nervous system.
• (ortho)sympathetic nervous system - fight or flight.
Prepares for action/stressful situations. Increases pressure and heart rate.
• Parasympathetic nervuos system- rest and digest.
Makes sure the blood pressure and heart rate come back to normal levels,
makes sure the food is digested well.
• They are different but work well together.
• The lines show how the nerves get to the
different organs and how they get back to the
CNS. It shows how the nerves innervate
• The parasympathetic nerves enter the CNS in
a neural cervicle ganglis or in a sacral
segments of the spinal chord (high in the neck
or low in the back). Bulbo (III, VII, IX, X) -
Sacral Ganglia in/on target organ
While sympathetic are more in the middle so
more in the thorax and lumbar sections.
Thoraco - Lumbar Ganglia in paravertebral
chain
It all has to do with what organs they
innervate.
• The parasympathetic is the anabolic system, it calms down the body (the rest
we take after eating is also part of this- to digest better the food)
Sympathetic (fighr or flight) is a catabolic system (burns down nutrients to
produce ATP- you need energy); so it prepares the body for action.
• There is also a difference in the neurotransmitter used to communicate through
the signals:
• Parasympathetic uses Acetylcholine
• Sympathetic uses noradrenaline/ norepinephrine. If adrenaline is released, the
body gets ready for action.
, • The system make use of long neurons:
• Parasympathetic has a long pre-synaptic neuron getting to the small circles in
the image (which represent a ganglion- cluster of nerve cells).
It has long neurons before getting to the ganglion. The ganglia are closely
located to the organs.
Long pre-synaptic neuron → ganglion (synapse) → second neuron (shorter)
to the organ system
• Sympathetic uses a chain of ganglia: long vertical chain of all clausters of
nerve cells getting together where they release neurotransmitters and
transmit signals from CNS to the PNS.
It has short pre-synaptic neurons and long post-synaptiuc neurons.
Pharmacology (neurotransmitters and receptors)
Neurotransmitters nervous system
• The white matter is the axons going down the
spinal chord (and then into the periphery).
• The somatic neurons move from CNS to a
muscle, where they release a neurotrasmitter
to make sure the muscle contracts
• The parasympathetic neuron innervates many
organs. There is a long pre-synaptic neuron,
which then meets a ganglion (a synapse happens),
the pre-synaptic neuron releases a signal that
activates the post-synaptic neuron, which then moves to the organ systems to
transmit the signal to induce an effect.
• 1st sympathetic neuron: usual structre, goes to many tissues
• 2nd: same as the 1st but uses a different neurotransmitter. If you sweat, it's
regulated by the cholinergic system(parasympathetic neurotransmitter)
• Adrenal medulla (produces noradrenaline and adrenaline):
sympathetic neurons that make use of parasympathetic neurotrasmitters.
Regulated by Ach
• All sympathetic pre-synaptic neurons use Ach and for the post it depends if it’s
somatic, parasympathetic, or sympathetic
• We make use of 2 types of neurotransmitters (acetylcholine or noradrenaline):
2 different systems
Cholinergic system: uses actelycholine
• Contains a choline group (can also
be absorbed by group) put with an
acetyl group.
• It mimicks quite well the effect of 2
exogenous compounds: nicotine
(smoke) and muscarine
(mushrooms).
• Achetylcholine can activate 2
nicotinic receptors (Nm and Nn)
and 3 muscarinic receptors (M1,
M2, M3)
there are 5 but the 4 and 5 are not so known in the sense of what processes are
regulated by the receptors
