Autonomic Nervous System
Where is Acetylcholine released?
- All PNS preganglionic and postganglionic neurons - All SNS preganglionic neurons and most SNS postganglionic neurons to sweat glands -All motor neurons to skeletal muscles
Clinical uses of botulinum toxin (botox)
1) Strabismus (disorder of vision due to a deviation from normal orientation of one or both eyes so that both cannot be directed at the same object at the same time; squint; crossed eyes) 2) Severe primary axillary hyperhidrosis (excessive sweating) 3) Cervical dystonia (abnormal tone of tissue) 4) Prevention of chronic migraines, 5) OAB associated with a neurological condition Under FDA investigation for several disorders: Limb muscle pain, Back pain Cosmetic Use: Treat frown lines between the brows
List the neurotransmitter found in the Parasympathetic Nervous System
Acetylcholine
List the neurotransmitters found in the Somatic Nervous System
Acetylcholine
What neurotransmitter is found in both the Sympathetic Nervous System and the Parasympathetic Nervous System?
Acetylcholine
List the neurotransmitters found in the Sympathetic Nervous System
Acetylcholine, Norepinephrine, Epinephrine
The ANS uses what 3 neurotransmitters?
Acetylcholine, Norepinephrine, Epinephrine
What class of drugs are used to treat Benign Prostatic Hypertrophy? List drugs with class!
Adrenergic Receptor: alpha-Antagonists → alpha1 selective antagonists Tamsulosin[Flomax] Finasteride[Proscar 5mg]
Isoproterenol 1) Targeted Receptors 2) Effect on Body 3) Clinical Uses
Beta selective beta1 → cardiac stimulation beta2 → brochodilation Clinical Use: Increases contractility and cardiac output in hypotension, surgery, congestive heart failure (CHF), and cardiac arrest
Dobutamine 1) Targeted Receptors 2) Effect on Body 3) Clinical Uses
Beta selective (since it binds selectively to beta receptors, there are less AE) beta1 - cardiac stimulation (some alpha1) Clinical Use: Increases contractility and cardiac output in hypotension, surgery, congestive heart failure (CHF), and cardiac arrest
The Central Nervous System consists of what two sub components?
Brain and the Spinal Cord
What three classes of drugs are used to treat glaucoma? List drug with class!
Cholinergic Drugs - Pilocarpine Anticholinesterase Drugs - Echothiophate (phospholine iodide) Adrenergic Receptor Beta Antagonist (B-blockers) Drug - Timolol [Timoptic]
Which neurotransmitters can activate dopamine receptors?
Dopamine
Dopamine can activate which adrenergic receptors?
Dopamine can activate alpha1, beta1, and dopamine receptors
Name 1 Irreversible Anticholinesterase Drug
Echothiophate (phospholine iodide)
Beta2 Receptors respond to which neurotransmitter?
Epinephrine
Epinephrine can activate which adrenergic receptors?
Epinephrine can activate all alpha and beta receptors, but not dopamine receptors
Alpha2 Receptors respond to which neurotransmitters?
Epinephrine, Norepinephrine
Alpha1 Receptors respond to which neurotransmitters?
Epinephrine, Norepinephrine, Dopamine
Beta1 Receptors respond to which neurotransmitters?
Epinephrine, Norepinephrine, Dopamine
Name 2 Beta Selective Adrenergic Neurotransmitters
Isoproterenol Dobutamine
What receptor selectivity is most useful for treatment of overactive bladder?
M3 (Muscarinic subtype)
What is the MOA of nicotine, include where they can be found?
MOA: Depending on the dosage: activate nicotine receptors (low dosage) or inhibits (high doses) them at several sites (autonomic ganglia and adrenal medulla; carotid body; aortic arch and CNS) Nicotine receptors can also be found in the somatic motor system; neuromuscular junctions Mneumonic - AAACC
Discuss clinical uses of antimuscarinic drugs and list common clinical uses
MOA: block muscarinic receptors Mneumonic - AAAMIBO Asthma Anti-parkinson Antispasmodic Motion Sickness Incontinence (OAB) Bradyarrhythmias Opthalmology
What is Tolterodine [Detrol] used for?
MOA: non-selectively blocks M2 and M3 receptors Clinical Use: Overactive Bladder Therapy (OAB)
What is Oxybutynin [Ditropan] and Darifenacin [Enablex] used for?
MOA: selectively blocks M3 receptors (highly selective) . Clinical Use: Overactive Bladder Therapy (OAB)
List non clinical uses for anticholinesterase drugs
Malathion (insecticide), sarin (nerve gas)
Explain the somatic (motor) nervous system in terms of neurotransmitters made and released by the nerves?
Motor neurons release ACh to excite and cause skeletal muscle fibers to contract (voluntary control; note that baroreceptor reflexes are controlled by the ANS)
List 3 clinical uses of anticholinesterase drugs? Name drugs with clinical use.
Myasthenia Gravis therapy (with Neostigmine [Prostigmin] or Edrophonium [Tensilon]) Alzheimer's disease therapy (with Donepezil [Aricept]) Glaucoma therapy with Echothiophate (phospholine iodide)
Name 3 Reversible Anticholinesterase Drugs
Neostigmine [Prostigmin], Edrophonium [Tensilon], Donepezil [Aricept]
Norepinephrine can activate which adrenergic receptors?
Norepinephrine can activate alpha1, alpha2, and beta1 receptors, but not beta2 or dopamine receptors
MOA of botulinum toxin (botox) What produces it?
Produced by Clostridium botulinum MOA: Act pre-synaptically --> inhibit Ach release at the NMJ --> cause temporary local paralysis of injected muscle (Effects last weeks to several months)
Where is Epinephrine released?
Released by Adrenal Medulla (when stimulated by ACh released by Sympathetic Nervous System pre-ganglionic neurons)
Where is Norepinephrine released?
Released by most postganglionic neurons of the Sympathetic Nervous System (except those that innervate sweat glands)
The Peripheral Nervous System consists of what two sub components?
Somatic (Motor) Nervous System and the Autonomic Nervous System
The Autonomic Nervous System consists of which two sub components?
Sympathetic Nervous System and the Parasympathetic Nervous System
Catecholamines Drugs are also called?
Sympathomimetic drugs
What classes of drugs are used to treat Hypertension? List drugs with class! Which one is an agonist?
Sympathomimetic drugs: Non-Catecholamines a. Clonidine[Catapres] **** this is the only agonist **** Adrenergic Receptor: alpha-Antagonists → alpha1 selective antagonists Prazosin [Minipres] Terazosin [Hytrin] Adrenergic Receptor beta-Antagonists: beta blockers Nonselective beta1 and beta2 → Propanolol [Inderal] Selective beta1 → Metoprolol [Lopressor] Partial agonist → Pindolol Non-selective Beta-blockade with Alpha-blockade → Labetrolol
Do anticholinesterase drugs increase or decrease the amount of acetlycholine at the synapse? Include MOA in answer
They increase the amount of acetylcholine at the synapse MOA: Inhibit AchE (acetylcholinestrase), the enzyme that degrades acetylcholine
Explain the pharmacodynamics of norepineprhine (slide on the powerpoint)
Tyrosine (tyrosine hydroxylase) --> DOPA (DOPA decarboxylase) --> Dopamine (dopamine beta hydroxylase) --> norepinephrine (MAO and COMT) - Stored in storage vesicules - Released following depolarization - Inactivated by Monoamine oxiade (MAO) and COMT or uptake into vesicles for reuse
Norepinephrine [Levophed] 1) Targeted Receptors 2) Effect on Body 3) Clinical Uses
binds to alpha1, alpha2, beta1 alpha → vasoconstriction beta1 → cardiac stimulation Clinical Use: hypotensive state, cardiac arrest
Epinephrine 1) Targeted Receptors 2) Effect on Body 3) Clinical Uses
binds to alpha1, alpha2, beta1, beta2 beta1 → cardiac stimulation (@ the heart) beta2 → bronchodilation (@ the lungs) alpha → constriction of arterioles Clinical Use: Acute hypersensitivity reactions [EpiPen], cardiac stimulant, in combination w/local anesthetics (the addition of epinephrine is useful to prolong the duration of anesthesia
Dopamine 1) Targeted Receptors 2) Effect on Body 3) Clinical Uses
binds to alpha1, beta1, dopamine receptors MOA: stimulates dopamine receptors → vasodilation of renal and mesenteric arteries Clinical Use: hypotension and shock
Beta2 receptors are useful for what?
bronchial dilation; uterine muscle relaxation; vasodilation; glycogenolysis
Which Andrenergic Agonist(s) is most useful for Hypotension?
dopamine-selective β₁-selective α₁-selective (some) Dobutamine Isoproterenol Norepinephrine[Levophed] Dopamine
Beta1 receptors are useful for what?
heart: ↑HR, ↑force of contraction, ↑ velocity of AV nodes conduction kidney: renin release
Alpha2 receptors are useful for what?
minimal clinical significance, located in presynaptic junction
Alpha1 receptors are useful for what?
vasoconstriction of arterioles; ejaculation; bladder neck + prostate contraction
Which Andrenergic Agonist is most useful for Decongestants?
α₁-selective Phenylephrine
Which Andrenergic Agonist(s) is most useful for Cardiac Stimulation?
β₁-selective α₁ -selective (some) Epinephrine Norepinephrine Dobutamine Isoproterenol
Which Andrenergic Agonist is most useful for Bronchodilation?
β₂-selective
Which Andrenergic Agonist is most useful for Uterine Relaxation?
β₂-selective
What effect does nicotine have on the CNS?
•CNS stimulant - Multiple psychological effects: facilitate memory, suppress appetite - Moderate can cause tremor, and high doses can cause convulsions
What effect does nicotine have on the Cardiovascular system?
•Results from the activation of nicotine receptors in ganglia of SNS and adrenal medulla -Elicits discharge of epinephrine from the adrenal medulla -Vasoconstriction = Increase in BP and HR -These effects underlie cardiovascular death
What effect does nicotine have on the GI system?
•Results from the activation of nicotinic receptors in ganglia - Increase GI tone and can promote vomiting