Drugs Affecting the Autonomic Nervous System
1. Describe the two divisions of ANS and explain how they differ
+Objective: ANS is divided into 2 divisions:
- Parasympathetic (peace/rest/relax)
- Sympathetic (stress/fight/flight)
• Parasympathetic nerves originate from:
- Cranial and sacral spinal nerves also called the craniosacral division • Sympathetic nerves originate
from:
- Thoracic and lumbar spinal nerves - also called the thoracolumbar division
• Almost all visceral organs and glands receive:a nerve branch from each division
* each organ has both receptors so we can rest when we need to - one calms/one stresses
Difference: One division INCREASES the activity of the gland or organ while the other division DECREASES activity
2.+WHAT IS THE AUTONOMIC NERVOUS SYSTEM?: The Autonomic Nervous System (ANS) is
the involuntary division of the nervous system. It consists of autonomic neurons that conduct impulses from the central nervous
system (brain and/or spinal cord) to glands, smooth muscle and cardiac muscle. ANS neurons are responsible for regulating the
secretions of certain glands (i.e., salivary glands) and the regulation of heart rate and peristalsis
(contraction of smooth muscle in the digestive tract), among other functions
3.+WHAT IS THE ROLE OF AUTONOMIC NERVOUS SYSTEM?: The role of the ANS is to constantly fine-tune the functioning of
organs and organ systems according to both internal and external stimuli. The ANS helps to maintain homeostasis (internal
stability and balance) through the coordination of various activities such as hormone secretion, circulation, respiration,
digestion and excretion. The ANS is always "on" and functioning unconsciously, so we are unaware of the important tasks it is
performing every waking (and sleeping) minute of every day.
4.Explain how sympathetic and parasympathetic nerves interact with each other to regulate organ function (maintain
Homeostasis).
+Objective: The sympathetic and parasympathetic nervous systems have opposite responses on body tissues and organs. different
neurotransmitters released by post synaptic neurons and different receptors in plasma membrane receptors
PNS • Parasympathetic nervous system
- Maintains homeostasis
- Works in "opposition" of the SNS
- "Rest and Digest"
• PARASYMPATHETIC - Cholinergic (parasympathomimetic) -
MIMICS THE PARASYMPATHETIC NERVOUS SYSTEM in contrast
with
- Cholinergic blocking (parasympatholytic)
, Drugs Affecting the Autonomic Nervous System
5. Describe the fight or flight reaction and explain how it affects the activities of the different organs.
+Objective: SNS • Sympathetic nervous system
- Fight or Flight
- Useful in highly stressful or emergency situations
• SYMPATHETIC
- Adrenergic (sympathomimetic) •
MIMICS THE SYMPATHETIC SYSTEM
in contrast with
• Adrenergic blocking (sympatholytic)
6.+Body Tissue/Organ
Sympathetic Response
'Stress-Fight-Flight': Eye - dilates pupil
Lungs - dilates bronchioles - b-2
Heart - increase heart rate - b-1
Blood vessels - constricts blood vessels - a-1
GI - relaxes smooth muscles of GI tract
Bladder - relaxes bladder muscle
Uterus - relaxes uterine muscle
7.Body Tissue/Organ
Parasympathetic Response
'Peace-Rest-Relax': Eye - constricts pupil
Lungs - constricts bronchioles and increases secretions
Heart - decreases heart rate
Blood vessels - dilates blood vessels
GI - increases peristalsis of GI tract
Bladder - constricts bladder muscle
Salivary gland - increases salivation
8.+WHAT ARE ADRENERGIC NERVE FIBERS?: An adrenergic nerve fibre is a neuron for which the neurotransmitter is either
adrenaline (epinephrine), noradrenaline or dopamine.
Adrenergic nerve terminals are found in the secondary neurons of the sympathetic nervous system (SNS), controlling amongst
other things heart rate and force of contraction.
ADRENERGIC RECEPTORS
9.Explain how the adrenergic nerve endings function both to release and inactivate norepinephrine.
, Drugs Affecting the Autonomic Nervous System
+Objective: Adrenergic/Sympathetic NEUROTRANSMITTERS (neurohormones)
CATECHOLAMINES - when nerve is agitated, they are secreted
- Epinephrine (prototype) - secreted by Adrenal gland (medulla) at top of kidney, direct response at nerve ending
- Norepinephrine - secreted by Adrenal gland. Stored @ cleft in the axon, direct response at the nerve ending as well - NE and EPI
are inactivated by neuronal reuptake back into the nerve ending for reuse or metabolism by Monoamine oxidase (MAO)
**RED**
10. +DRUG PROTOTYPE: A representative drug from a drug class, it is usually the most studied member of each class and
other drugs in that class are noted merely for their differences when compared to it. It eases the learning of pharmacology
Most prescribed drug
11. +* Monoamine oxidase (MAO): very important
- NE and EPI are inactivated by neuronal reuptake back into the nerve ending for reuse or metabolism by Monoamine oxidase
(MAO) **RED**
12. +RECEPTORS / RECEPTOR SITES: ALPHA 1 - vasoconstriction/sm contraction ALPHA 2 - decreases NE and
therefore BP
BETA 1 - mostly dominant on heart BETA 2 - mostly
dominant on lungs there are more, but prof. notes these
are enough...
13. +RECEPTOR Responses to Stimulation: ALPHA 2 (located on presynaptic terminal)
- **RED** Control the release of norepinephrine *
notes: works in CNS
Axon
*neurotransmitter stored in vesicles
*neurotransmitter released into synapse
Enzymes in cleft destroy neurotransmitter
*** or ***
Dendrite (on)
Neurotransmitter attaches to receptor
14. P0-Name the three (3) different adrenergic receptors and describe the actions they mediate
+Objective: dopomine, NE, EPI alpha 1,2 , beta
1,2 , dopomine
a1 - dilates eyes, vessels, bladder
a2 - decreases insulin, neurotransmitter in neuromuscular junctions
1. Describe the two divisions of ANS and explain how they differ
+Objective: ANS is divided into 2 divisions:
- Parasympathetic (peace/rest/relax)
- Sympathetic (stress/fight/flight)
• Parasympathetic nerves originate from:
- Cranial and sacral spinal nerves also called the craniosacral division • Sympathetic nerves originate
from:
- Thoracic and lumbar spinal nerves - also called the thoracolumbar division
• Almost all visceral organs and glands receive:a nerve branch from each division
* each organ has both receptors so we can rest when we need to - one calms/one stresses
Difference: One division INCREASES the activity of the gland or organ while the other division DECREASES activity
2.+WHAT IS THE AUTONOMIC NERVOUS SYSTEM?: The Autonomic Nervous System (ANS) is
the involuntary division of the nervous system. It consists of autonomic neurons that conduct impulses from the central nervous
system (brain and/or spinal cord) to glands, smooth muscle and cardiac muscle. ANS neurons are responsible for regulating the
secretions of certain glands (i.e., salivary glands) and the regulation of heart rate and peristalsis
(contraction of smooth muscle in the digestive tract), among other functions
3.+WHAT IS THE ROLE OF AUTONOMIC NERVOUS SYSTEM?: The role of the ANS is to constantly fine-tune the functioning of
organs and organ systems according to both internal and external stimuli. The ANS helps to maintain homeostasis (internal
stability and balance) through the coordination of various activities such as hormone secretion, circulation, respiration,
digestion and excretion. The ANS is always "on" and functioning unconsciously, so we are unaware of the important tasks it is
performing every waking (and sleeping) minute of every day.
4.Explain how sympathetic and parasympathetic nerves interact with each other to regulate organ function (maintain
Homeostasis).
+Objective: The sympathetic and parasympathetic nervous systems have opposite responses on body tissues and organs. different
neurotransmitters released by post synaptic neurons and different receptors in plasma membrane receptors
PNS • Parasympathetic nervous system
- Maintains homeostasis
- Works in "opposition" of the SNS
- "Rest and Digest"
• PARASYMPATHETIC - Cholinergic (parasympathomimetic) -
MIMICS THE PARASYMPATHETIC NERVOUS SYSTEM in contrast
with
- Cholinergic blocking (parasympatholytic)
, Drugs Affecting the Autonomic Nervous System
5. Describe the fight or flight reaction and explain how it affects the activities of the different organs.
+Objective: SNS • Sympathetic nervous system
- Fight or Flight
- Useful in highly stressful or emergency situations
• SYMPATHETIC
- Adrenergic (sympathomimetic) •
MIMICS THE SYMPATHETIC SYSTEM
in contrast with
• Adrenergic blocking (sympatholytic)
6.+Body Tissue/Organ
Sympathetic Response
'Stress-Fight-Flight': Eye - dilates pupil
Lungs - dilates bronchioles - b-2
Heart - increase heart rate - b-1
Blood vessels - constricts blood vessels - a-1
GI - relaxes smooth muscles of GI tract
Bladder - relaxes bladder muscle
Uterus - relaxes uterine muscle
7.Body Tissue/Organ
Parasympathetic Response
'Peace-Rest-Relax': Eye - constricts pupil
Lungs - constricts bronchioles and increases secretions
Heart - decreases heart rate
Blood vessels - dilates blood vessels
GI - increases peristalsis of GI tract
Bladder - constricts bladder muscle
Salivary gland - increases salivation
8.+WHAT ARE ADRENERGIC NERVE FIBERS?: An adrenergic nerve fibre is a neuron for which the neurotransmitter is either
adrenaline (epinephrine), noradrenaline or dopamine.
Adrenergic nerve terminals are found in the secondary neurons of the sympathetic nervous system (SNS), controlling amongst
other things heart rate and force of contraction.
ADRENERGIC RECEPTORS
9.Explain how the adrenergic nerve endings function both to release and inactivate norepinephrine.
, Drugs Affecting the Autonomic Nervous System
+Objective: Adrenergic/Sympathetic NEUROTRANSMITTERS (neurohormones)
CATECHOLAMINES - when nerve is agitated, they are secreted
- Epinephrine (prototype) - secreted by Adrenal gland (medulla) at top of kidney, direct response at nerve ending
- Norepinephrine - secreted by Adrenal gland. Stored @ cleft in the axon, direct response at the nerve ending as well - NE and EPI
are inactivated by neuronal reuptake back into the nerve ending for reuse or metabolism by Monoamine oxidase (MAO)
**RED**
10. +DRUG PROTOTYPE: A representative drug from a drug class, it is usually the most studied member of each class and
other drugs in that class are noted merely for their differences when compared to it. It eases the learning of pharmacology
Most prescribed drug
11. +* Monoamine oxidase (MAO): very important
- NE and EPI are inactivated by neuronal reuptake back into the nerve ending for reuse or metabolism by Monoamine oxidase
(MAO) **RED**
12. +RECEPTORS / RECEPTOR SITES: ALPHA 1 - vasoconstriction/sm contraction ALPHA 2 - decreases NE and
therefore BP
BETA 1 - mostly dominant on heart BETA 2 - mostly
dominant on lungs there are more, but prof. notes these
are enough...
13. +RECEPTOR Responses to Stimulation: ALPHA 2 (located on presynaptic terminal)
- **RED** Control the release of norepinephrine *
notes: works in CNS
Axon
*neurotransmitter stored in vesicles
*neurotransmitter released into synapse
Enzymes in cleft destroy neurotransmitter
*** or ***
Dendrite (on)
Neurotransmitter attaches to receptor
14. P0-Name the three (3) different adrenergic receptors and describe the actions they mediate
+Objective: dopomine, NE, EPI alpha 1,2 , beta
1,2 , dopomine
a1 - dilates eyes, vessels, bladder
a2 - decreases insulin, neurotransmitter in neuromuscular junctions
