PMC EXAM 1 QUESTIONS AND ANSWERS
Describe Autonomic Nervous System (ANS). What are autonomic functions? - Answers
:ANS functions are not under direct conscious control (happen without thinking). E.g.
Cardiac function, endothelial function, digestion, blood flow to organs etc.
What is a neurotransmitter? - Answers :a chemical substance that is released at the end
of a nerve fiber by the arrival of a nerve impulse and, by diffusing across the synapse or
junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or
some other structure.
Discuss anatomy of the ANS. What are ganglions? Where are they located? Receptors
and their location, and effector organs. - Answers :the ganglion is a cluster of neural
bodies outside the central nervous system. It contains Nicotinic receptors, and acts ups
the sympathetic system (ie. Sweat glands, Cardiac and smooth muscles, and renal
vascular smooth muscles.
Discuss Sympathetic & parasympathetic NS. Fight or Flight reactions. - Answers :The
never fibers originate from two different sections of the spinal cord and terminate in the
effector organs. The parasympathetic fibers originate in the medulla and are responsible
for "rest and digest" functions. The sympathetic nervous system is responsible for "fight
or flight reactions." Adrenergic receptors are involved. However, in the sweat glands -
cholinergic receptors. Flight or Fight: Increase NE, Heart rate increases, more energy,
more sugar in the blood (glycogen gets converted to glucose), decreased gut
movement, increased blood supply to muscles, so you can respond to the situation.
Cholinergic neurotransmission: - Answers :the primary transmitter is Acetylcholine
(Ach). Almost all fibers leaving from CNS are cholinergic
Adrenergic neurotransmission - Answers :the primary transmitter is norepinephrine.
Discuss cholinergic neurotransmission. What are the receptors? Where do they
located? What is the function of those receptors? What is the main neurotransmitter
molecule? What is a synapse? What happens in the synaptic cleft? - Answers :Synaptic
Cleft
1. Ach is made inside the nerve terminal from 2 components (Acetyl CoA and Choline)
2. Ach is released to the synaptic cleft & binds the choline receptors in the postsynaptic
cell and brings the effect.
3. Unbound Ach get broken down to 2 components (choline + acetate) by an enzyme
called Acetyl Cholinesterase.
4. Several places for drug action
,Discuss adrenergic receptors, their location and functions. What are the
neurotransmitters in adrenergic NS? - Answers :Adrenergic neurotransmission involves
production of catecholamine transmitters. They are norepinephrine, dopamine, and
adrenalin (epinephrine). The biosynthesis of catecholamine involves following steps:
Tyrosine -> Dopa -> Dopamine -> Norepinephrine -> Epinephrine
The processes in Catecholamine biosynthesis and metabolism are potential sites for
drug action.
Discuss what happens in the cholinergic synapse in detail? Ach production, storage,
release. What are the enzymes involved? Which enzyme is involved in which step? -
Answers :1. Ach is made inside the nerve terminal from 2 components (Acetyl CoA and
Choline)
2. Ach is released to the synaptic cleft & binds the choline receptors in the postsynaptic
cell and brings the effect.
3. Unbound Ach get broken down to 2 components (choline + acetate) by an enzyme
called Acetyl Cholinesterase.
4. Several places for drug action
Discuss the function of acetyl cholinesterase enzyme. What happens when you block
acetyl cholinesterase? - Answers :Unbound Ach get broken down to 2 components
(choline + acetate) by an enzyme called Acetyl Cholinesterase. If this enzyme is
blocked or "inhibited", there will be more ACh remaining in the synaptic cleft for a longer
period of time, allowing more actions to occur
Discuss cholinergic functions briefly - Answers :Signal start from brain / spinal cord,
signals transmit through nerves to distal parts of the body. There is a chemical called
neurotransmitter involves in this transmission of signals. Chemical transmission takes
place between the nerve cell and their effectors (could be another nerve, or tissue) in
the place call synaptic cleft. The transmitter binds the receptors in the post synaptic cell
and activate or inhibit it. Drugs can mimic or block the actions of these transmitters & in
turn can modify these autonomic functions.
Discuss potential sites of drug action in cholinergic neurotransmission. - Answers
:Drugs can inhibit choline transport to the nerve ending (e.g. Hemicholiniums).
Drugs can inhibit Ach transport to the vesicle (e.g. Vesamicol)
Agents / drugs can block Ach binding to cholinoreceptors (e.g. cholinoreceptor blocker,
Atropine)
Drugs that mimic Ach (cholinomimetic drugs, such as Bethanechol).
,Agents / drugs can block acetyl cholinesterase enzyme so Ach is available longer (e.g.
Cholinesterase inhibitors such as Malathion).
Agents / drugs can inhibit Ca channel so Ach vesicles can't fuse with the surface
membrane (e.g. Verapamil)
Agents / drugs can inhibit Ach vesicles fusion with the surface membrane and emptying
Ach to the cleft (e.g. Botulinum toxin)
12 - Answers :
Discuss potential site of drug action. - Answers :Drugs can inhibit choline transport to
the nerve ending (e.g. Hemicholiniums).
Drugs can inhibit Ach transport to the vesicle (e.g. Vesamicol)
Agents / drugs can block Ach binding to cholinoreceptors
(e.g. cholinoreceptor blocker, Atropine)
Drugs that mimic Ach (cholinomimetic drugs, such as Bethanechol). Agents / drugs can
block acetyl cholinesterase enzyme so Ach is available longer (e.g. Cholinesterase
inhibitors such as Malathion).
Agents / drugs can inhibit Ca channel so Ach vesicles can't fuse with the surface
membrane (e.g. Verapamil )
Agents / drugs can inhibit Ach vesicles fusion with the surface membrane and emptying
Ach to the cleft (e.g. Botulinum toxin)
Discuss two types of cholinomimetic drugs? - Answers :-Direct acting drugs bind the
receptor and mimics or modulate the effect of Ach.
-Indirect acting drugs inhibits the acetylcholinesterase enzyme so Ach can't be broken
down, so Ach level increases.
Discuss direct acting cholinomimetics. Name 2 kinds? - Answers :Choline esters &
Alkaloids.
Ach belongs to? - Answers :Cholinergic neurotransmitter?????
Discuss hydrolysis of Ach?
Is it quick or take long time? - Answers :Ach is broken down to two parts, acetate +
choline using water by the cholinesterase enzyme.
quick
, What is the enzyme involved in hydrolysis of Ach? - Answers :Cholinesterase
What is the neurotransmitter involved in cholinergic neurotransmission? - Answers
:Acetylcholine
What are the neurotransmitters involved in adrenergic neurotransmission? - Answers
:Norepinephrine, epinephrine, and dopamine
Discuss cholinergic receptor subtypes: Nicotinic and Muscarinic. - Answers :Muscarinic
- G protein coupled, receptors
Nicotinic - signaling via ion channel, receptors
Nicotinic and Muscarinic location - Answers :Muscarinic- located in CNS, endothelium,
heart, and smooth muscles.
Nicotinic- located in autonomic ganglia, and skeletal muscles.
Describe cholinomimetic / cholinergic receptor activating / Cholinergic receptor agonist
drugs. - Answers :Cholinomimetic drugs MIMIC Cholinergic Medications. Direct acting
drugs bind the receptor and mimics or modulate the effect of Ach. Indirectly acting drugs
inhibits the acetylcholinesterase enzyme so Ach can't be broken down, so Ach level
increases
Esters
Bethanechol
Carbachol
Methacholine
Alkaloids
Muscarine
Pilocarpine
Nicotine - Alkaloid, Agonist of nicotinic ACHR
All the others - Agonists of muscarinic receptor
Discuss target tissues - Answers :CNS have both muscarinic and nicotinic receptors.
Brain - more muscarinic receptors
Describe Autonomic Nervous System (ANS). What are autonomic functions? - Answers
:ANS functions are not under direct conscious control (happen without thinking). E.g.
Cardiac function, endothelial function, digestion, blood flow to organs etc.
What is a neurotransmitter? - Answers :a chemical substance that is released at the end
of a nerve fiber by the arrival of a nerve impulse and, by diffusing across the synapse or
junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or
some other structure.
Discuss anatomy of the ANS. What are ganglions? Where are they located? Receptors
and their location, and effector organs. - Answers :the ganglion is a cluster of neural
bodies outside the central nervous system. It contains Nicotinic receptors, and acts ups
the sympathetic system (ie. Sweat glands, Cardiac and smooth muscles, and renal
vascular smooth muscles.
Discuss Sympathetic & parasympathetic NS. Fight or Flight reactions. - Answers :The
never fibers originate from two different sections of the spinal cord and terminate in the
effector organs. The parasympathetic fibers originate in the medulla and are responsible
for "rest and digest" functions. The sympathetic nervous system is responsible for "fight
or flight reactions." Adrenergic receptors are involved. However, in the sweat glands -
cholinergic receptors. Flight or Fight: Increase NE, Heart rate increases, more energy,
more sugar in the blood (glycogen gets converted to glucose), decreased gut
movement, increased blood supply to muscles, so you can respond to the situation.
Cholinergic neurotransmission: - Answers :the primary transmitter is Acetylcholine
(Ach). Almost all fibers leaving from CNS are cholinergic
Adrenergic neurotransmission - Answers :the primary transmitter is norepinephrine.
Discuss cholinergic neurotransmission. What are the receptors? Where do they
located? What is the function of those receptors? What is the main neurotransmitter
molecule? What is a synapse? What happens in the synaptic cleft? - Answers :Synaptic
Cleft
1. Ach is made inside the nerve terminal from 2 components (Acetyl CoA and Choline)
2. Ach is released to the synaptic cleft & binds the choline receptors in the postsynaptic
cell and brings the effect.
3. Unbound Ach get broken down to 2 components (choline + acetate) by an enzyme
called Acetyl Cholinesterase.
4. Several places for drug action
,Discuss adrenergic receptors, their location and functions. What are the
neurotransmitters in adrenergic NS? - Answers :Adrenergic neurotransmission involves
production of catecholamine transmitters. They are norepinephrine, dopamine, and
adrenalin (epinephrine). The biosynthesis of catecholamine involves following steps:
Tyrosine -> Dopa -> Dopamine -> Norepinephrine -> Epinephrine
The processes in Catecholamine biosynthesis and metabolism are potential sites for
drug action.
Discuss what happens in the cholinergic synapse in detail? Ach production, storage,
release. What are the enzymes involved? Which enzyme is involved in which step? -
Answers :1. Ach is made inside the nerve terminal from 2 components (Acetyl CoA and
Choline)
2. Ach is released to the synaptic cleft & binds the choline receptors in the postsynaptic
cell and brings the effect.
3. Unbound Ach get broken down to 2 components (choline + acetate) by an enzyme
called Acetyl Cholinesterase.
4. Several places for drug action
Discuss the function of acetyl cholinesterase enzyme. What happens when you block
acetyl cholinesterase? - Answers :Unbound Ach get broken down to 2 components
(choline + acetate) by an enzyme called Acetyl Cholinesterase. If this enzyme is
blocked or "inhibited", there will be more ACh remaining in the synaptic cleft for a longer
period of time, allowing more actions to occur
Discuss cholinergic functions briefly - Answers :Signal start from brain / spinal cord,
signals transmit through nerves to distal parts of the body. There is a chemical called
neurotransmitter involves in this transmission of signals. Chemical transmission takes
place between the nerve cell and their effectors (could be another nerve, or tissue) in
the place call synaptic cleft. The transmitter binds the receptors in the post synaptic cell
and activate or inhibit it. Drugs can mimic or block the actions of these transmitters & in
turn can modify these autonomic functions.
Discuss potential sites of drug action in cholinergic neurotransmission. - Answers
:Drugs can inhibit choline transport to the nerve ending (e.g. Hemicholiniums).
Drugs can inhibit Ach transport to the vesicle (e.g. Vesamicol)
Agents / drugs can block Ach binding to cholinoreceptors (e.g. cholinoreceptor blocker,
Atropine)
Drugs that mimic Ach (cholinomimetic drugs, such as Bethanechol).
,Agents / drugs can block acetyl cholinesterase enzyme so Ach is available longer (e.g.
Cholinesterase inhibitors such as Malathion).
Agents / drugs can inhibit Ca channel so Ach vesicles can't fuse with the surface
membrane (e.g. Verapamil)
Agents / drugs can inhibit Ach vesicles fusion with the surface membrane and emptying
Ach to the cleft (e.g. Botulinum toxin)
12 - Answers :
Discuss potential site of drug action. - Answers :Drugs can inhibit choline transport to
the nerve ending (e.g. Hemicholiniums).
Drugs can inhibit Ach transport to the vesicle (e.g. Vesamicol)
Agents / drugs can block Ach binding to cholinoreceptors
(e.g. cholinoreceptor blocker, Atropine)
Drugs that mimic Ach (cholinomimetic drugs, such as Bethanechol). Agents / drugs can
block acetyl cholinesterase enzyme so Ach is available longer (e.g. Cholinesterase
inhibitors such as Malathion).
Agents / drugs can inhibit Ca channel so Ach vesicles can't fuse with the surface
membrane (e.g. Verapamil )
Agents / drugs can inhibit Ach vesicles fusion with the surface membrane and emptying
Ach to the cleft (e.g. Botulinum toxin)
Discuss two types of cholinomimetic drugs? - Answers :-Direct acting drugs bind the
receptor and mimics or modulate the effect of Ach.
-Indirect acting drugs inhibits the acetylcholinesterase enzyme so Ach can't be broken
down, so Ach level increases.
Discuss direct acting cholinomimetics. Name 2 kinds? - Answers :Choline esters &
Alkaloids.
Ach belongs to? - Answers :Cholinergic neurotransmitter?????
Discuss hydrolysis of Ach?
Is it quick or take long time? - Answers :Ach is broken down to two parts, acetate +
choline using water by the cholinesterase enzyme.
quick
, What is the enzyme involved in hydrolysis of Ach? - Answers :Cholinesterase
What is the neurotransmitter involved in cholinergic neurotransmission? - Answers
:Acetylcholine
What are the neurotransmitters involved in adrenergic neurotransmission? - Answers
:Norepinephrine, epinephrine, and dopamine
Discuss cholinergic receptor subtypes: Nicotinic and Muscarinic. - Answers :Muscarinic
- G protein coupled, receptors
Nicotinic - signaling via ion channel, receptors
Nicotinic and Muscarinic location - Answers :Muscarinic- located in CNS, endothelium,
heart, and smooth muscles.
Nicotinic- located in autonomic ganglia, and skeletal muscles.
Describe cholinomimetic / cholinergic receptor activating / Cholinergic receptor agonist
drugs. - Answers :Cholinomimetic drugs MIMIC Cholinergic Medications. Direct acting
drugs bind the receptor and mimics or modulate the effect of Ach. Indirectly acting drugs
inhibits the acetylcholinesterase enzyme so Ach can't be broken down, so Ach level
increases
Esters
Bethanechol
Carbachol
Methacholine
Alkaloids
Muscarine
Pilocarpine
Nicotine - Alkaloid, Agonist of nicotinic ACHR
All the others - Agonists of muscarinic receptor
Discuss target tissues - Answers :CNS have both muscarinic and nicotinic receptors.
Brain - more muscarinic receptors
