Def The ANS consists of all visceral motor neurons innervating smooth muscle cardiac muscle and glands Divide Autonomic Pharmacology into Four Categories 1 Drugs that increase the sympathetic nervous system response ID: 670587
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The Autonomic Nervous System
Def: The ANS consists of all visceral motor neurons innervating smooth muscle, cardiac muscle and glands.Slide2
Divide Autonomic Pharmacology into Four Categories:
1. Drugs that increase the sympathetic nervous system response
2. Drugs that increase the parasympathetic response
3. Drugs that block the sympathetic nervous system response
4. Drugs that block the parasympathetic response Slide3
Sympathetic Nervous System Adrenaline Rush Autonomic nervous system response to fear, anger, stress Slide4
Parasympathetic Nervous System Rest and Digest Relax, Repair, Renew Slide5
Sympathetic Parasympathetic
Agonist
Antagonist Slide6
Sympathetic Parasympathetic
Agonist
Antagonist Slide7
Sympathetic Parasympathetic
Agonist
Antagonist Slide8
Autonomic Nervous System Autonomic means automatic You do not control your ANS, it works automatically
Controls the functions of MANY organs automatically That’s why many drugs that affect the ANS affect many organs Slide9
Drugs that increase the sympathetic nervous system response.
Sympathomimetic – mimic, imitate the sympathetic nervous system response Slide10
Drugs that increase the parasympathetic nervous system response.
Parasympathomimetic – mimic, imitate the parasympathetic nervous system response Slide11
Drugs that decrease the sympathetic nervous system response.
Sympatholytic – decrease or block the sympathetic nervous system response Slide12
Drugs that decrease the parasympathetic nervous system response.
Parasympatholytic – decrease or block parasympathetic nervous system response Slide13
Drugs that affect the ANS will affect many organs:
Heart Lung airways Blood vessels Bowels
Pancreas Ureters Bladder Eyes Pupils
Lacrimal gland
Salivary glands Slide14
Do not confuse the autonomic nervous system with: Peripheral Nervous System Outside of skull and spinal cord
Neurons end on organs and muscle
Central Nervous System Brain and spinal cord Neurons end on other neurons Slide15
Do not confuse the ANS with Voluntary Nervous System Voluntary means willing, like to volunteer You do control your voluntary nervous system
You control your skeletal muscles to move your body Slide16
The autonomic nervous system is divided into two systems: Sympathetic
Adrenaline rush Fear, flight, fight Slide17
B. Parasympathetic rest, repair, digest Slide18
Can you guess what is happening to this girl’s organ function?Slide19
Running is voluntary in this case (she has no choice)
But everything else is automatic
Effects of epinephrine or adrenalin
(heart is pounding)Slide20
Adrenergic Receptors Heart is innervated by sympathetic neurons Norepinephrine – comes from the sympathetic neuron
The heart senses Adrenaline from Adrenal gland on top of the kidneysEpinephrine is adrenalin
Adrenergic Beta 1 receptors Slide21
Effects of Epinephrine – Adrenaline
Lung Airways WIDE OPEN BP is high – systemic vessels constrict Slide22
Adrenergic Receptors Blood vessel smooth muscle is innervated by sympathetic neuron Norepinephrine
Receptors also sense adrenaline from adrenal Epinephrine
Adrenergic Alpha 1 receptors Slide23
Adrenergic Receptors Lung bronchiole smooth muscle is innervated by sympathetic neuron Norepinephrine
Blood vessels sense adrenaline from adrenal Epinephrine
Adrenergic Beta 2 Receptors Slide24
Effects of Epinephrine – Adrenalin Blood to muscles increased Blood to GI decreased
Pupils dilated
Norepinephrine – neurotransmitter that dilates lungs, constricts blood vessels, lung airways open, shutting down GI tract Slide25
Why are all these changes occuring? Sympathetic nervous system (Norepinephrine)
Adrenal gland – on top of kidneys (that extra boost) Adrenalin (Epinephrine)
Adrenergic Neurons or Adrenergic Agonist Adrenergic System Slide26Slide27
Adrenergic Agonists Adrenergic Agonist substances are also called
sympathomimetics Slide28
Epinephrine or Adrenaline Adrenaline is an adrenergic agonist
- increased heart rate - constricts blood vessels
- dilates lung airways - dilates pupils Slide29
Albuterol Is an adrenergic beta agonist used in asthma, what are some of its other effects besides bronchodilation
?Increased heart rate Increased blood pressure Slide30
Adrenergic Antagonists Beta blockers are common drugs used to treat high blood pressure Beta blockers are common drugs used to treat high eye pressures (glaucoma) Slide31
Asthma Do you understand why beta blockers can make asthma worse?That’s why one of the reasons we try to use
cardioselective beta blockers in patients with asthma Slide32
Autonomic Nervous System Although we have discussed many organ functions We have only discussed HALF of the Autonomic Nervous System
The other half does the opposite Slide33
Can you guess what is happening to his heart rate? His blood pressure? Slide34
Effects of parasympathethic tone
This is the rest and digest system - Acetylcholine – neurotransmitter - Muscurinic receptors
Slide35
Parasympathetic Nervous System
Cholinergic Agonism Cholinomimetic
Rx: Bethanecol - cholinergic muscurinic agonist - used to stimulate bowel and bladder function
Slide36
Indirect Cholinergic Agonism Acetylcholinesterase
inhibitors Blocking the breakdown of acetylcholine increases acetylcholine levels Acetylcholineterase
inhibitors are cholinomimeticRx: Neostygmine Toxin: Organophosphate – acetylcholinesterase inhibitors
Slide37
Cholinergic Antagonism Rx: Atropine – classic cholinergic antagonist
Cholinergic muscuranic antagonist Anticholinergic
Antimuscuranic Slide38
Rx: Atropine
Speeds up heart rate
Emergency treatment for
bradycardia
(slow heart rate)
Atropine also causes
mydriasis
Atropine used for
diarrhea
Atropine used as antidote for organophosphate poisoning Slide39
Asthma Beta agonists are used in asthma
But so are cholinergic
muscuranic blockers Slide40
DuoNeb
for Asthma contain two drugs
Rx:
Albuterol
– beta2 agonist
- sympathomimetic
Rx: Ipratropium – anticholinergic
-
antimuscarinic
-
parasympatholytic
Slide41
Heart rate up or down Blood pressure up or down
Eye pressure up or down Lung airways open or closed
Bladder relax or less relaxed GI stimulate or slow Slide42
Dilating the pupils is – Mydriasis Slide43
Dilating the pupils is – Mydriasis
Both
Sympathomimetic adrenergic drugs
and
Anticholinergic
parasympatholytic
drugs
cause
mydriasis
Slide44
Constricting the pupils is Miosis Slide45
Both sympatholytic adrenergic antagonist drugs and
- Cholinergic parasympathomimetic drugs cause miosis Slide46
Dry lacrimal glands Both sympathomimetic adrenergic drugs
And Anticholinergic parasympatholytic drugs
Cause dry eyes Slide47
Stimulate lacrimal glands to make tears Both sympatholytic adrenergic antagonist drugs
and Cholinergic parasympathomimetic
drugs Stimulate tear production Slide48
Dries salivary glands
Both sympathomimetic adrenergic drugs And Anticholinergic parasympatholytic drugs
Cause dry mouth Slide49
Stimulates salivary glands to make saliva Both sympatholytic adrenergic antagonist drugs
and Cholinergic parasympathomimetic
drugs Stimulate saliva production Slide50
Both sympathomimetic adrenergic drugs
And Anticholinergic parasympatholytic drugs
Dry respiratory airways Slide51
Both sympatholytic adrenergic antagonist drugs
And cholinergic parasympathomimetic drugs Can stimulate airway secretion Slide52
Bronchodilation: relaxing bronchiole smooth muscle to open airways
Both sympathomimetic adrenergic drugs and
Anticholinergic parasympatholytic drugs Cause bronchodilation and are used in asthma Slide53
Bronchoconstriction/Bronchospasm: contracting bronchiole smooth muscle to close or constrict airways Slide54
Both sympatholytic adrenergic antagonist drugs
And Cholinergic parasympathomimetic drugs
Can cause bronchospasm Slide55
Drugs that cause tachycardia (fast heart rate) are called positive chronotropes
Both sympathomimetic adrenergic drugs
And Anticholinergic parasympatholytic drugs Cause tachycardia Slide56
Drugs that increase the force of contraction are positive inotropes Slide57
Sympathomimetic adrenergic drugs are positive inotropes Slide58
Drugs that cause bradycardia (slow heart rate) are called negative chronotropes Slide59
Both sympatholytic adrenergic antagonist drugs
And Cholinergic parasympathomimetic drugs can cause bradycardia Slide60
Drugs that decrease the force of contraction are negative inotropes Slide61
Sympatholytic adrenergic antagonist drugs are negative inotropes Slide62
Vasoconstriction: contracting arteriole smooth muscle to raise blood pressure Slide63
Sympathomimetic adrenergic drugs raise blood pressure by vasoconstriction Slide64
Vasodilation: relaxing arteriole smooth muscle to drop blood pressure Slide65
Sympatholytic adrenergic antagonist drugs can drop blood pressure Slide66
Some drugs relax the GI tract and slow peristalsis Slide67
Both sympathomimetic adrenergic drugs
And Anticholinergic parasympatholytic drugs
Slow peristalsis, relax GI Slide68
Some drugs stimulate peristalsis in the GI tract Slide69
Cholinergic parasympathomimetic drugs are used to stimulate GI Slide70
Drugs that affect autonomic nervous system may affect the pancreas Slide71
Some drugs relax the bladder and urinary tract smooth muscle and slow peristalsis Slide72
Both sympathomimetic adrenergic drugs and anticholinergic parasympatholytic drugs slow ureter peristalsis and relax bladder Slide73
Some drugs stimulate the smooth muscle of the bladder and urinary tract, increasing peristalsis Slide74
Cholinergic parasympathomimetic drugs are used to stimulate the bladder Slide75
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76
Sympathetic and Parasympathetic Divisions of the ANS
How they are similar:
Both divisions are part of the ANS
Both have effects on smooth muscle, cardiac muscle and glands
How they differ:
Stimulation of effectors by each system vary from one body system to another. Effects may be stimulatory or inhibitory.
Location
Length of pre and postganglionic fiber
Neurotransmitters usedSlide77
77
Comparison of ANS and Somatic Motor Pathways
Somatics
Single neuron from spinal cord to effector
One neuron innervates the effector cell
NTS is acetylcholine (ACh)
Autonomics
Two neurons relay (ganglion) to effector
Dual innervation of effectors
NTS at ganglia (ACh); NTS at effector can be ACh or norepinephrine Slide78
Location and neurotransmitters used by Sympathetic/Parasymp
sympathetic
parasympathetic
preganglionic neuron
postganglionic neuron
nicotinic receptors
muscarinic receptors
adrenergic receptorsSlide79
Characteristics of Sympathetic and Parasympathetic FunctionPost-ganglionic sympathetic nerves release norepinephrine at their nerve endingsthese nerves are called adrenergic nervesPre and post-ganglionic parasympathetic nerves release acetylcholine at their nerve endings (Nitric oxide- corpora cavernosa)these nerves are called cholinergic nervesEXCEPTION FOR SYMPATHETIC:Cholinergic: mACH; used in body wall.Vasodilation of vessels in brain and skeletal muscle Piloerector muscles
Sweat glandsNitric oxide: vasodilation of vessels in brain, skeletal muscleSlide80
80
Sympathetic
Nervous System
“Thoracolumbar”
Figure 60-1;
Guyton & Hall
When active?
Length of pre and postganglionic nerve?
Location of cell bodies of preganglionic nerve?
Location of cell bodies of postganglionic nerve?
Neurotransmitters released?
Adrenal medullaSlide81
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Lipolysis and thermogenesis
Adipose tissue
3
Inhibitory, relaxation of resp. tract to get dilation
Respiratory tract
, GI, glands, hepatocytes
2
Increased heart rate and inotropy
HEART
, kidney, adipocytes
1
Presynaptic control/ release of NT
Vascular endothelium
2c
Increase vasoconstriction (increased MI mortality w/polymorphism)
Vascular endothelium
2b
Lipid metabolism
Vascular endothelium and adipocytes
2a
Increased BP, vasoconstriction
Arteries
, heart
1B
Increased inotropy, closure of GI sphincters, vasoconstriction, pupil dilation
Iris
,
intestine
, heart and arteries
1a
Actions
Where found?
ReceptorSlide82
82
Parasympathetic
Nervous System
“cranio-sacral”
Parasympathetic nerves originate from cranial nerves III, VII, IX, and X and the sacral spinal cord.
occulomotor nerve
- fibers to the pupillary sphincters and ciliary muscle
facial nerve
- fibers to lacrimal and submandibular gland
glossopharyngeal nerve
- fibers to parotid gland
vagus nerve
- motor inputs to visceral organs
sacral segments
- fibers to descending colon, rectum, bladder and genitalia
Figure 60-3;
Guyton & HallSlide83
Effects of the ANS on the Organseyesympathetic --pupillary dilation (alpha 1 receptor)parasympathetic--pupillary constriction and accommodation (focusing) of the lens (mACh receptor)glands of the bodyparasympathetic stimulate the nasal, lacrimal, salivary, and G.I. glands (mACh receptor)sympathetic stimulates the sweat glands (mACh receptor)Slide84
Effect of the Autonomic Nervous System on the OrgansG.I. tractparasympathetic stimulates overall activity including G.I. smooth musclesympathetic has very little effectheartsympathetic increases the rate and contractilityparasympathetic decreases heart rateblood vesselssympathetic causes vasoconstriction. Reduced sympathetic response accounts for most vasodilation.parasympathetic causes some vasodilation (e.g., penis)Slide85
Sympathetic and Parasympathetic “Tone”the basal rate of activity of each systemthis background activity allows for an increase or decrease in activity by a single system sympathetic tone normally causes about a 50 % vasoconstrictionincreasing or decreasing “tone” can change vessel diameterparasympathetic tone provides background G.I. activitySlide86
adrenergic or sympathomimetic drugs act like norepinephrinethese drugs have an effect which is much more prolonged than that of either norepinephrine phenylephrine stimulates alpha receptorsisoproterenol stimulates both beta1 and beta2 receptorsalbuterol stimulates only beta2 receptorssome drugs act indirectly by increasing the release of norepi from its storage terminalsephedrine, amphetamine, pseudoephedrine, Slide87
Pharmacology of the Sympathetic Nervous Systemdrugs that block the effect of norepinephrine alpha blockersphentolamine Cheap Viagra!beta blockersbeta1 and 2 - propranololSlide88
Pharmacology of the Parasympathetic Nervous Systemparasympathomimetic drugsmuscarinepilocarpineactivates muscarinic receptors, cause profuse sweating (why if sweat glands are controlled by sympathetic system?)cholinesterase inhibitorsneostigmine, potentiates the effect of acetylcholineantimuscarinic drugsatropine blocks the effect of acetylcholine on effector cells