The Nervous System Flashcards
Substrate (or Ligand)
A substance that creates a signal or produces an effect by binding to a receptor, enzyme or transporter.
Endogenous
A substance that is produced by the body.
(such as a naturally produced substrate)
Exogenous
A substance that is produced outside of the body (such as a drug or other chemical)
Agonist
A substance that combines with a receptor to initiate a reaction.
Can be endogenous or exogenous (mimicking an endogenous substrate)
Antagonist
A substance that reduces or blocks a reaction.
Can be endogenous or exogenous
Induction
When a substance increases the activity of an enzyme
Inhibition
when a substance decreases or blocks the activity of an enzyme
The (CNS) Central Nervous System comprises of :
the brain & spinal cord
The CNS is like a command center, which sends signals to the ________
(PNS) Peripheral Nervous System
The PNS consists of:
all the neural tissue outside of the brain and spinal cord
When the CNS sends signals to the PNS, these signals are going to create some end effect in __________
an organ, muscle, tissue, or gland
Signals are transmitted from the CNS to PNS in the form of using __________
neurotransmitters
The PNS comprises of 2 main ___________. The _______ and ________
systems
somatic nervous system
autonomic nervous system
Somatic nervous system
voluntary controls muscle movement
Autonomic nervous system
involuntary controls other bodily functions, such as digestion, cardiac output and blood pressure
presynaptic neuron sends the ___ and a postsynaptic neuron receives the
signal
signal
The signal or chemical messenger is an __________
endogenous neurotransmitters
“naturally produced in the body”
Common neurotransmitters
(ACh) Acetylcholine
(NE) norepinephrine
(Epi) epinephrine
(DA) dopamine
(5-HT) serotonin
What is the primary neurotransmitter responsible in the somatic nervous system and binds to nicotinic (Nn) receptors in skeletal muscle?
ACh - acetylcholine
________ are the body’s chemical messengers.
neurotransmitters (NTs)
Neurotransmitters are released from the _________ and into the __________. Neurotransmitters then travel to _____________
presynaptic neurons
synaptic cleft
post synaptic neurons or other parts of the body to exert their effect.
___________ is the primary neurotransmitter involved in the somatic nervous system
ACh - acetylcholine
what are the 2 main divisions of the autonomic nervous system?
Sympathetic - fight or flight
Parasympathetic - rest or digest
_________ is the primary neurotransmitter involved in the autonomic nervous system
ACh - acetylcholine
Acetylcholine acts on ____________ receptors to propagate signal transmission forward in synaptic sites or act at a terminal site like the adrenal medulla or skeletal muscle.
ACh also acts on _________ receptors
Nn - nicotinic receptors
muscarinic receptors
In the parasympathetic nervous system, the physiologic response is carried out when acetylcholine binds to _____________
muscarinic receptors
In the sympathetic nervous system, the physiologic response is carried out when:
NT - ____________ binds to _______
NT-_____________ binds to ________
NT-_____________ binds to_________
NE - norepinephrine ——————- alpha and beta receptors
ACh - acetylcholine ——————— Muscarinic receptors
Ach - acetylcholine ——————– Nicotinic receptors
The release of adRENergic neurotransmitters ________ and ______ are released from the adRENal medulla
EpinephRINe & NorepinephRINe
In the parasympathetic nervous system “rest or digest”, the primary neurotransmitter “chemical messenger” __________ acts on __________ receptors to propagate signals forward from CNS and then acts on _________ receptors to carry out a physiological response on____________.
(ACh) acetylcholine
Nicotinic receptors
Muscarinic receptors
smooth muscles & glands & most organs
When ______________ acts on Muscarinic receptors located throughout the body, including the GI tract and bladder, this creates a __________________ response. Those Symptoms being remembered as “SLUDD”
ACh - acetylcholine
rest & digest physiologic
SLUDD - Salivation/Lacrimation/Urination/Diarrhea/Digestion
so increased activity of SLUDD
peristalsis:
the involuntary constriction and relaxation of the muscles of the intestine, creating wave like movements, pushing the contents forward.
lacrimation:
the flow of tears
defecation:
the discharge of feces from the body
In the sympathetic nervous system “fight or flight”, the primary neurotransmitter “chemical messenger” _______________ acts on ____________ receptors to propagate signals forward from the CNS and on _________ receptors on the ____________ to cause a release of ___________.
These neurotransmitters then can travel throughout the body and act on __________
The _____________ neurotransmitter can also act on ___________ receptors, which leads to a physiologic response.
ACh - acetylcholine
Nicotinic receptors
Nicotinic receptors
adrenal medulla
adrenergic neurotransmitters = epinephrine & norepinephrine
adrenergic receptors (alpha-1, Beta-1, Beta-2)
ACh - acetylcholine
Muscarinic receptors
alpha -1 receptors are located ________
on the vasculature. so smooth muscles, blood vessels
Beta-1 receptors are located _______
in the heart “1 heart”
Beta-2 receptors are located ________
in the lungs “2 lungs”
The sympathetic nervous system “fight or flight” physiologic response is the _________ of the parasympathetic nervous system. So, we have decreased _______________ and increased __________________ when the adrenergic receptors are stimulated.
opposite
salivation/urination/peristalsis
pupil dilation/glucose production/HR/BP
adrenergic activity in the eye will increase pupil dilation.
Activation of adrenergic receptors in the GI tract(___________) is going to _______________
Beta-2 receptors
increase glucose production, So more energy is available for muscles “fight or flight response” stressful situation.
Activation of adrenergic receptors in the heart ( _________________) is going to _____________
Beta-1 receptors
increase HR and increase (CO) cardiac output, so more oxygen can be delivered to muscles and organs
Stimulation of the adrenergic receptors in the lungs (_________________) is going to ______________
Beta-2 receptors
cause bronchodilation, which is going to increase the amount of oxygen available to assist with this fight-or-flight response
Muscarinic receptors are located throughout the body, including on the________________________________
GI tract/bladder/eyes
When ______________ acts on Nicotinic receptors located throughout the body, in synaptic clefts/ on skeletal muscle/ on adrenal medulla, this creates a number of different responses.
what symptoms/response occurs with the previous mentioned areas?
ACh
A substance that is naturally produced in the body = ____________
endogenous
A substance that creates a signal or produces an effect by binding to a receptor, enzyme or transporter. =
Think of neurotransmitters in terms of substrates and ligands
A substance that is produced outside the body (such as a drug or chemical) =
exogenous
Common neurotransmitters to be familiar with that play a big role in drug treatment of CNS, these include: think “SEDAN”
-
-
-
- Serotonin (5-HT)
- Epinephrine (Epi)
- Dopamine (DA)
- Acetylcholine (ACh)
- Norepinephrine (NE)
others:
Glutamate (an excitatory neurotransmitter)
(CNS) Central nervous system:
includes the brain and spinal cord.
- this controls the functions of the rest of the body by sending signals to the PNS.
(PNS) Peripheral Nervous System:
Has 2 main parts- remember VISA
1)
2)
1) Somatic nervous system (Voluntary)
- controls muscle movements
2) Autonomic nervous system (Involuntary)
- here signals from the CNS are going to be transmitted to various organs, smooth muscles, and glands.
- controls other bodily functions, such as digestion, cardiac output, and blood pressure.
1) Voluntary
2) Involuntary
1) Somatic
2) Autonomic-
1) Ach
2)
The primary neurotransmitter in play for the Somatic nervous system is _____________. It is released in response to neuron signals and binds to ___________ in skeletal muscles to affect muscle movement.
(ACh) Acetylcholine
(Nn) Nicotinic receptors
The Autonomic Nervous System is also broken into 2 main divisions:
1)
2)
What are the primary neurotransmitters for each division?
Where do these neurotransmitters act on terminally?
The physiological response for each division is caused by what neurotransmitter? and what is it acting on?
1) sympathetic “fight or flight”
-primary neurotransmitter is (ACh)
- (ACh) acetylcholine acts at synapses or synaptic junctions binding to nicotinic receptors, in order to continue signal transmission OR act at a terminal site.
- - -
(ACh) acetylcholine acting on nicotinic receptors on the adrenal medulla causes adrenergic neurotransmitters (Epi) epinephrine and (NE) norepinephrine to be released.
(NE) norepinephrine AND (Epi) epinephrine can then go on causing a physiologic response by binding to adrenergic receptors [alpha-1, beta-1, and beta-2 receptors] in organs, smooth muscles and glands in order to elicit a sympathetic fight or flight response.
The physiologic response:
In the cardiovascular system and respiratory system.
- increased BP, HR and bronchodilation
- stimulation of beta-2 in the GI tract increases glucose production to provide muscles with oxygen and energy.
2) parasympathetic “rest or digest”
-primary neurotransmitter is (ACh)
- (ACh) acetylcholine acts at synapses or synaptic junctions binding to nicotinic receptors, in order to continue signal transmission OR act at a terminal site.
- - - (ACh) acetylcholine is further released, causing a physiologic response by binding to Muscarinic receptors located throughout the body, including GI tract (stomach), the bladder and the eyes. The physiologic response is known as (SLUDD) salivation, lacrimation, urination, defecation/diarrhea and digestion. ALL of these are increased when the parasympathetic nervous system is activated.
The primary neurotransmitter in play for the Autonomic Nervous System (for both divisions) and the Somatic Nervous System is __________.
(ACh) acetylcholine
(ACh) acetylcholine acts at synapses or synaptic junctions binding to nicotinic receptors, in order to continue signal transmission OR act at a terminal site such as the adrenal medulla or skeletal muscle.
(ACh) acetylcholine acting on nicotinic receptors on the adrenal medulla causes adrenergic neurotransmitters ___________.
epinephrine (Epi) AND norepinephrine (NE) to be released.
(ACh) acetylcholine acting on nicotinic receptors on skeletal muscle cause __________.
voluntary muscle movement
(Somatic nervous System)
The terminal sites affected in both the sympathetic and parasympathetic nervous system are the same.
-
-
But the physiological response and symptoms that occur when either system is activated differs because of the neurotransmitters and receptors involved.
- organs
- smooth muscles
- glands
alpha-1 = on peripheral vasculature, vascular smooth muscle
beta-1 = primarily on heart
beta-2 = lungs
Is the opposite of the parasympathetic response. Now the body has to respond to a stressful situation.
so you have decreased salivation, urination and decreased peristalsis.
adrenergic activity in the eye: increases in pupil dilation.
activation of adrenergic receptors in the GI tract: increases in glucose production, to provide muscles with oxygen and energy.
activation of adrenergic receptors in the peripheral vasculature causes vasoconstriction. Increasing blood pressure
Activation of adrenergic receptors in the heart is going to increase heart rate and cardiac output, so more blood can deliver more oxygen to muscles and organs.
Activation of adrenergic receptors in lungs causes bronchodilation. This increases the amount of oxygen available to assist with fight or flight response.
