• What are the basic mechanisms by which neuropharmocologic agents act?
o Can modify the disease process
o Act at the sites of actions which is the axons versus synapses and steps in
synaptic transmission and effects of drugs on the steps of synaptic transmission
• Transmittter synthesis is the first step in transmission. What are the other 4 steps?
o Transmitter storage, transmitter release, receptor binding, and termination of
the transmission
• True or False: Neuropharmacologic drugs have high selectivity.
o True—the nervous system uses many different receptor types
• Information needed:
o Type of receptors—through which the drug acts
▪ Alpha and beta
o Normal responses to the activation of those receptors
▪ Agonists vs. antagonists
o What the drug in questions does to the receptor function
• What are the 3 functions of ANS?
o Regulates the heart
o Regulates the secretory glands, saliva glands, gastric, sweat, and bronchial
o It regulates smooth muscles: bronchi, blood vessels, urogenital system, and the GI tract
• What are the regulatory functions of the parasympathetic NS?
o Seven regulatory functions
▪ Slowing the heart rate
▪ Increasing the gastric secretions
▪ Emptying the bladder
▪ Emptying the bowel
▪ Focusing the eye for near vision,
▪ Constricting the pupil
▪ Contracting the bronchial smooth muscle
o It also regulates the digestion of food, excretion of waste, control of vision
and conservation of energy
• What are the functions of the sympathetic NS?
o Regulation of the cardiovascular system
▪ Maintaining blood flow to the brain
▪ Redistributing blood and compensating for the loss of blood
o Regulation of body temperature
▪ Regulates blood flow to the skin
▪ Promotes the secretion of sweat
▪ Induces piloerection (erection of the hair)
o Implementation of the fight or flight reaction
▪ Increase HR and BP
▪ Blood shuts away from the skin and visera
▪ Bronchi dilate
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, ▪ Pupils dilate
▪ Use energy that had been stored
• What is the baroreceptor reflex?
o The receptors near the heart monitor BP changes and send the information to the brain
o The brain then activates the Autonomic NS to restore blood pressure to normal
o When BP falls, this reflex causes vasoconstriction and increases cardiac output.
o When BP rises, it causes vasodilation and reduces cardiac output
• Where is acetylcholine employed?
o Most junctions at the peripheral nervous system
• Where is epinephrine and norepinephrine released?
o Norepinephrine—postganglionic neurons
o Epinephrine—adrenal medulla
• What are the cholinergic receptors mediated by? What are the subtypes?
o Receptors that mediate responses to acetylcholine
o Subtypes:
▪ Nicotinic
▪ Muscarinic
• Whare are adrenergic receptors mediated by? What are the subtypes?
o Mediate responses to epinephrine and norepinephrine
o Subtypes:
▪ Alphas
▪ Betas
▪ Dopamine
• What are the functions of each adrenergic subtype?
o Alpha 1—vasoconstriction, ejaculation and contraction of the bladder neck, and prostate
o Alpha 2—(located in presynaptic junction)—minimal clinical significance
o Beta 1—control the heart
▪ Increase HR, increase force of contraction and velocity of conduction in the
AV node; stimulate renin released in the kidney
o Beta 2—bronchial dilation, relaxation of the uterine muscle, vasodilation, glycogenolysis
o Dopamine—dilates renal blood vessels
• Epinephrine can activate all alpha and beta receptors but not dopamine receptors
• Norepinephrine can activate alpha1, alpha2, and beta receptors but not beta2 or
dopamine receptors
• Dopamine can activate alpha1, beta1 and dopamine receptors
• Muscarinic agonists mimic the effects of acetylcholine at muscarinic receptors
• Muscarinic antagonists selectively blood the effects of acetylcholine (and other
muscarinic agonists) at muscarinic receptors
• What are therapeutic uses of Bethanechol?
o Urinary retention
o Investigational GI uses—off label GI reflux
• What are actions on smooth muscle, exocrine glands, and eye?
o Smooth muscle—
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, ▪ lung by causing constriction of the bronchi
▪ the GI system by increasing tone and motility
▪ the bladder by contraction of the detrusor muscle
▪ relaxation of the trigone and sphincter
o Exocrine glands—increased sweating salivation, bronchial secretions and secretion
of gastric acid
o Eye—causes miosis and contraction of the ciliary muscle
• Adverse Effects?
o Hypotension
o Abdominal cramps
o Diarrhea
o Increased salivation
o Exacerbate asthma
o Can cause dysrhythmias in patients with hyperthyroidism
• What are cevimeline, pilocarpine, and acetylcholine used for?
o Cevimeline—treat dry mouth and Sjogren’s syndrome
o Pilocarpine—topical treatment of glaucoma as well as dry mouth from
Sjogren’s syndrome
o Acetylcholine—rapid myosis after delivery and cataract surgery
• Anticholinergics
o Competitively block the actions of acetylcholine as muscarinic receptors
o Most muscarinic receptors are on structures innervated by parasympathetic nerves
o Also known as parasympatholytic drugs, antimuscarinic drugs, muscarinic blockers,
and anticholinergic drugs
o Anticholinergic drugs: produce selective blockade of the muscarinic receptors (not
all cholinergic receptors)
o Can’t pee, see, spit or shit
• What are the pharmacologic effects of atropine?
o The heart—increases in rate
o The exocrine glands—decrease secretions
o Smooth muscle—relaxes the bronchi, decreases the tone of the urinary bladder
detrusor and decreases the tone motility of the GI tract
o Mydriasis and cycloplegia in the eyes
o Mild excitation to hallucinations and delirium in the Central Nervous system
• Therapeutic Uses of Atropine?
o Pre-anesthetic medication to help dry up secretions
o Disorders of the eye
o In codes for bradycardia, intestinal hypertonicity and hypermotility
o Muscarinic agonist poisoning
o Peptic ulcer disease
o Asthma
o Biliary colic
• Side effects of Atropine
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, o Dry mouth
o Blurred vision
o Photophobia
o Elevation of interocular pressure
o Urinary retention
o Constipation anhidrosis
o Tachycardia
o Asthma
• Overactive bladder
o Oxybutyin—acts on M3 muscarinic receptors
▪ Highly lipid soluble
▪ Metabolized CYP3A4
▪ Very short ½ life and must be dosed frequently
o Darifenacine—
▪ Can reduce OAB symptoms while having no effect or M1 receptors in the
brain or M2 receptors in the heart
▪ Greatest degree of M3 selectivity
o Solifenacin—at high dose can prolong QT interval
o Tolterodine—nonselective muscarinic antagonist
o Fesoterodine—nonselective muscarinic antagonist
o Trospium-nonselective muscarinic antagonist
• Scopalamine
o Uses?
▪ Motion sickness
▪ Production of a cytoplegia and mydriasis for ophthalmic procedures
▪ Production of pre-anesthetic sedation and obstetric amnesia
o Side effects?
▪ Xerostomia (dry mouth)
▪ Blurred vision
▪ Photophobia
▪ Urinary retention
▪ Constipation
▪ Hyperthermia
▪ Tachycardia
• Ipratropium Bromide
o Uses?
▪ Treat asthma, COPD and rhinitis caused by allergies or common cold
o Side effects?
▪ Not associated with typical anti-muscarinic side effects
• What are mydriatic cycloplegics?
o Atropine, homatropine, scopolamine, cyclopentolate and tropicamide
o Used to produce mydriasis and cyclopedia in ophthalmic procedures
• Muscarinic Poisoning
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