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Pharm 09 test 1
By Drew
72
Medical
Graduate
08/20/2009

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Term
Which postganglionic sympathetic neurons are not adrenergic
Definition
Those that release Dopamine and sympathetic innervation of the eccrine (thermoregulatory) sweat glands,
which is cholinergic!
Term
Dopamine can act on what type of receptors
Definition
D1, D2 and alpha and Beta receptors
Term
What enzyme catalyzes the reactions of L-Dopa to dopamine
Definition
aromatic amino acid decarboxylase
Term
What enzyme catalyzes the reaction of NE to epinephrine
Definition
phenyl-N-methyl-transferase
Term
What enzyme catalyzes the step of dopamine to NE
Definition
dopamine β-hydroxylase
Term
Primary means of inactivation of catecholamines
Definition
Reuptake into nerve terminals
Term
Catechol-O-Methyl-Transferase (COMT)
Definition
is located extracellularly on
membranes throughout the body. It can therefore metabolize released
catecholamines into inactive metabolites.
Term
α-1
Definition
Critical alpha-1 distribution is in the radial muscle of the iris, the
vasculature, and the genitourinary (α-1a) and gastrointestinal sphincters.
Activation of these receptors causes contraction of the muscle.
Term
α-2
Definition
1. Also located in the vasculature, although they play a less critical role
than the alpha-1.
2. Located on NE nerve terminals. So function as inhibitory
autoreceptors. That is, activation of these receptors decreases the
amount of NE released.
3. Located in the brainstem where activation leads to decreased
sympathetic and increased parasympathetic nervous system
activation.
** Points 2 and 3 are important for understanding why alpha-2 agonists
are considered anti-adrenergic.
Term
Relative affinities of b2 for epi and NE
Definition
100 fold greater affinity for Epi
Term
Beta-1
Definition
receptors are important because of their localization to cardiac muscle.
1. Activation leads to increased conduction and contractility in the heart.
2. Therefore, beta-1 receptor activation increases cardiac output.
Term
beta-2
Definition
Mediate vasodilation in skeletal muscle, bronchiodilation, and relaxation of bladder and uterine walls
Term
D1 receptors
Definition
Increase GFR, Sodium excretion and renal blood flow. causes vasodilation in renal, cardiac, cerebral, and mesenteric vasculature.
Term
What is the Main autonomic determinant
of vascular tone/total peripheral resistance.
Definition
Alpha 1 activation which causes vasoconstriction
Term
Parasympathetic effects on total peripheral resistance
Definition
Parasympathetic nervous system activation will not
alter total peripheral resistance, but direct-acting muscarinic agonists can.
Term
What effect does alpha1 activation have on intraocular pressure
Definition
decreases blood flow to ciliary body and trabecular
network. Decreases production and increases outflow of aqueous humor.
Term
What effect does alpha 2 activation have on intraocular pressure
Definition
decreases production of aqueous humor and increases outflow of aqueous humor.
Term
What effect does beta 1 activation have on intraocular pressure
Definition
increases the production of aqueous humor
Term
What effect does beta 2 activation have on intraocular pressure
Definition
increases aqueous humor production and increases outflow of aqueous humor
Term
What effect does muscarinic activation have on intraocular pressure
Definition
causes contraction of ciliary muscle. Tension on trabecular network leads to increased outflow of aqueous humor
through the network.
Term
What mediates sympathetic Regulation of the Bronchioles and what effects does it have
Definition
Beta-2 mediated. 1. Bronchodilation 2. Incresed cilial beat frequency 3. decreased vascular permeability 4. Inhibits release of inflammatory mediators from mast cells
Term
Effects of parasympathetic Regulation of the Bronchioles
Definition
Constricts bronchioles and increases mucous secretions
Term
Effects of sympathetic Regulation of the Urinary Bladder
Definition
Alpha 1a - Constricts sphincter and prostate as well as prostate capsule
Beta 2 - Relaxtion of bladder wall (detrusor muscle)
Term
Parasympathetic Regulation of the Urinary Bladder
Definition
Muscarinic activation causes relaxation of sphincter and contraction of bladder wall
Term
What are the majority of cholinergic receptors in the CNS
Definition
95% Muscarinic, 5% Nicotinic Nueral
Term
What is the response to Cholinergic CNS stimulation
Definition
Mimics peripheral sympathetic effects, Increase blood pressure, heart rate, pupil dilation. Cognitive -- confusion, altered memory, coma. Motor -- Initial tremors followed by convulsion
Term
Acetyl choline as a drug
Definition
Rapidly degraded <20 sec. Stimulates both nicotinic and muscarinc receptors. Clinically usefeul in settings where rapid stimulation/degradation is necessary i.e. cataract surgery.
Term
Bethanechol
Definition
(1) Synthetic carbamoyl choline ester.
(2) Long acting-NOT hydrolyzed by ChEs
(3) Only stimulates muscarinic
Term
Carbachol
Definition
(1) synthetic carbamoyl choline ester
(2) Long acting-NOT hydrolyzed by ChEs.
(3) Stimulates BOTH muscarinic and nicotinic
(4) causes release of ACh from synapses
Term
Cevimeline (Evoxac)
Definition
(1) Recently (2000) approved
(2) Selective for M3
receptors
Term
Pilocarpine
Definition
(1) Plant alkaloid
(2) only muscarinic
Term
ChE inhibitors act by what mechanism
Definition
ChE inhibitors, except the organophosphates, are competitive
inhibitors of ChE.
Term
Edrophonium and Ambenonium
Definition
ChE inhibitors (1) Brief duration min (Edrophonium) to hrs (Ambenonium)
(2) electrostatic forces and hydrogen bonding.
(3) reversible
Term
Neostigmine,
physostigmine,
pyridostigmine
Definition
ChE inhibitors. Binding mechanism similar to ACh. Longer duration 0.5-6 hrs.
Term
Organophosphates—Isoflurophate and
echothiophate
Definition
(1) phosphorylate active site of ChE forming a phosphoryl-enzyme
complex
(2) very slowly reverses (hundreds of hours).
(3) With time bond strength increases -“ages”, and the phosphoryl-
ChE link becomes essentially irreversible.
(4) Need synthesis of new ChE.
Term
Which ChE inhibitors do not cross the BBB
Definition
Neostigmine, edrophonium, pyridostigmine, & ambenonium & Echothiophate
Term
Which ChE inhibitors do cross the BBB
Definition
Physostigmine, Isoflurophate, insecticides, & nerve gases
Term
Which drugs would be used to treat myasthenia gravis
Definition
Long-Term Oral Rx Is With ChE Inhibitors that Don’t cross the BBB:
Neostigmine (short duration [2-4 hr])
Pyridostigmine (3-6 or 6-8 hr [sustained release])
Ambenonium (3-8 hr)
Term
Drugs used for treatment of Glaucoma
Definition
(1) topical (pilocarpine, carbachol) or (echothiophate, 2nd choice due to side effects)
Term
Drugs used to treat xerostomia (dry mouth)
Definition
(1) Pilocarpine-
(2) Cevimeline- M3 selective, longer lasting, fewer side effects
Term
Treatment of choice for urinary bladder atony
Definition
Treatment-cholinomimetic or ChE Inhibitor
(1) bethanecol- M3 selective
(2) neostigmine- relatively short duration (2-4 hr)
Term
Neuromuscular blockade during surgery
Definition
Treatment- ChE Inhibitor of moderate duration
(1) Neostigmine- increases ACh in neuromuscular junction to
overcome competitive blockade
Term
treatment for Intoxication by Antimuscarinic Agents i.e. (1) Poisoning with atropine, antihistamines, tricyclic antidepressants
Definition
Physostigmine is the drug of choice
(a) crosses the blood-brain barrier
(b) reverse many of the central and peripheral effects of poisoning
by atropine and related antimuscarinic agents.
(c) can cause seizures.
Term
What are the four drugs used to treat alzeimers
Definition
Tacrine, Donepezil, Rivastigmine, Galantamine
Term
Tacrine
Definition
Used to treat alzeimers disease (a) modest increase in cognitive function.
(b) can cause reversible liver damage (30-50%)
(c) Cholinergic side effects that they can also limit use.
(d) no longer widely used in clinical practice.
Term
Donepezil
Definition
produces modest improvement in some
measures of cognitive function in patients with Alzheimer’s disease.
(a) more selective to CNS ChE, less toxic
(b) long duration of action – single dose/day is possible
Term
Rivastigmine and galantamine
Definition
Recently FDA approved to treat alzeimers. (b) Long-acting, but given twice daily
(c) Pattern of toxicities is less severe, like donepezil, but still
includes nausea, vomiting, diarrhea, and insomnia.
(d) Efficacy similar to that of donepezil
Term
Three primary contraindications of cholinomimetics
Definition
Asthma, Coronary insufficiency and peptic ulcers.
Term
By what mechanism do antimuscarinics work?
Definition
Competitive antagonists at the muscarinic receptor.
Term
Prototypical antimuscarinic drugs
Definition
Atropine and scopolamine, atropine only crosses BBB at higher doses.
Term
Tropicamide
Definition
antimuscarinic. Like a short acting atropine used in opthalmic exams to help dilate pupil. Lasts about 6 hours
Term
What drug is used in conjunction with antimuscarinic during opthalmic exams to help dilate the pupil. What receptor does it act upon
Definition
Phenylephrine. Alpha-adrenergic agonist.
Term
What use do antimuscarinics have in presurgery patients
Definition
Stops the heart rate from decreasing too much. Not routine. Used in patients in danger of cardiac slowing i.e. downs syndrome patients
Term
What are antimuscarinics used for in post surgical patients
Definition
ChE inhibitors are sometimes used to help stop neuromuscular blockade after surgery by increasing ACh at nicotinic and muscarinic synapses. In this case Antimuscarinic drugs can be coadministered to prevent unwanted side effects of muscarinic activation
Term
Pralidoxime
Definition
Used as a ChE reactivator from organophosphate poisoning. Must be applied within hours of poisoning
Term
Drug of choice for organophosphate poisoning
Definition
Atropine. Also given with Pralidoxime
Term
Tolterodine
Definition
Selective M3 antagonist. Used for urinary urgency/incontinence and bed wetting. Relaxes detrusor and tightens sphincter.
Term
Solifenacin
Definition
New drug, relatively selective for M3, used like Tolterodine but with less side effects (especially dry mouth)and a little more efficacy.
Term
Drug of choice for motion sickness and what side effects does it have
Definition
Scopolamine patch. Can cause dry mouth, drowsiness Rare serious CNS effectsdepression,
amnesia, excitation, psychotic episodes
Term
Two drugs that can be used for Bronchospasms
Definition
Ipratropium: inhalant antimuscarinic, not very selective. Not absorbed well so it doesn't produce many side effects. Lasts 4-6 hrs longer if given with an Alpha 2 agonist
Tiotropium: Like ipratropium but lasts longer 24 hr duration and is selective for M1 and M3
Term
Treatment of Parkinsons disease
Definition
Usually levodopa or carbidopa but antimuscarinics were used prior to there development to decrease the cholinergic input and restore balance between excitatory and inhibitory signals. Still can be used in some populations to control tremors but mostly as a secondary treatment due to side effects.
Term
Antimuscarinic contraindications / precautions
Definition
Glaucoma
Obstructive or paralytic GI disease
Myasthenia gravis
Antimuscarinics contraindicated in
pathological conditions where blockade of PSNS or skeletal muscle system receptors would worsen symptoms.
Term
Treatment for antimuscarinic toxicity and symptoms.
Definition
Treat with ChE inhibitors(physostigmine), remove source, gastric lavage, diazepam is used to reduce CNS mediated convulsions. Symptoms: Blind as a bat, dry as a bone, red as a beet, hot as a hare, and mad as a hatter
Term
By what mechanism do organophosphates work
Definition
Bind ChE
Term
ACh agonists
Definition
Acetylcholine,
Bethanechol,
Carbachol,
Cevimeline,
Pilocarpine
Term
short acting AChesterase inhibitors
Definition
Edrophonium,
Ambenonium
Term
Longer acting ACh esterase inhibitors
Definition
Neostigmine,
Physostigmine,
Pyridostigmine,
Term
Irreversible ACh esterase inhibitors
Definition
Isoflurophate,
Echothiophate
Term
Alzheimers drugs
Definition
Tacrine(not used much),
Donepezil,
Rivastigmine,
Galantamine,
Term
Antimuscarinic drugs
Definition
Atropine,
Scopolamine,
Tropicamide,
Tolterodine (used for urinary incontinence and bedwetting),
Solifenacin and Oxybutynin (urinary incontinence),
Ipratropium and Tiotroprium (Bronchospasms),
Glycopyrrolate
Term
ChE reactivator
Definition
Pralidoxime
Term
The Alzheimers drugs act by what mechanism
Definition
They are ACh esterase inhibitors
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