ANS Pharmacology

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What is the order of affinity of EPI, NE, and ISO on alpha receptors?: EPI > NE >> ISO
What is the order of affinity of EPI, NE, and ISO on beta-1 receptors?: ISO > EPI = NE
What is the order of affinity of EPI, NE, and ISO on beta-2 receptors?: ISO > EPI >> NE
What are the cardiovascular effects of Isoproterenol?: Heart:
â†‘ Rate
â†‘ Contractility

Vascular Smooth Muscle:
â†“ Peripheral Resistance
? Blood Pressure
What are the cardiovascular effects of Norepinephrine?: Heart:
â†‘ Rate (but then goes down b/c of vagal reflex)
â†‘ Contractility (but then goes down b/c of vagal reflex)

Vascular Smooth Muscle:
â†‘â†‘ Peripheral Resistance
â†‘â†‘ Blood Pressure
What is the reflex cardiovascular effect of NE?: â†“ Heart Rate
â†“ Contractility

Secondary to increase in BP -> strong vagal compensation overcomes direct effects on heart
What are the cardiovascular effects of EPI?: Heart:
â†‘ Contractility
â†‘ Heart Rate

Vascular Smooth Muscle:
â†“ Peripheral Resistance
â†‘ BP (mean)
Indirect-acting phenylethylamines lack what group?: β-OH
Which stereoisomer of phenylethylamines is the active form?: L (or S)
What alteration to phenylethylamines greatly increases their oral effectiveness and duration of action?: Removal of one or both ring hydroxyls
What alteration to phenylethylamines allows them to cross the blood-brain barrier?: Removal of both ring hydroxyls
What alteration to phenylethylamines enhances their resistance to MAO?: Presence of an α-carbon substituent
What are the contraindications or reasons for caution in sympathomimetic therapy? (8): 1. Cardiac disease
2. HTN
3. Cerebral arteriosclerosis
4. DM
5. Hyperthyroidism
6. During general anesthesia with halothane or cyclopropane
7. Pregnancy
8. Pts receiving therapy w/ beta-receptor antagonists
Where in the cell is Acetyl CoA synthesized?: Mitochondria
Where do cholinergic cells store ACh?: In vesicles
In the cytoplasm
Where do AChE inhibitors act on the AChE molecule?: At the esteratic site
Where in the body are muscarinic receptors located?: Autonomic effector cells
Certain autonomic ganglion cells
CNS
Which receptor, muscarinic or nicotinic, has faster response time?: Nicotinic
What type of receptors are muscarinic receptors?: G-protein-linked
Activation of Mâ‚, Mâ‚ƒ, and Mâ‚… muscarinic receptors exerts what effect on cells?: â†‘ IPâ‚ƒ and DAG to â†‘ Caâºâº and Naâº
Causes increase in contraction and secretion
Activation of Mâ‚‚ and Mâ‚„ muscarinic receptors exerts what effect on cells?: Inhibition of cAMP formation
Increased K⁺ conductance
Decreased Ca⁺⁺ conductance
Where in the body are nicotinic receptors located?: Autonmoic ganglia
Skeletal muscle (NMJ)
CNS
What type of receptor are nicotinic receptors?: Ligand-gated ion channels
Cholinomimetics are routinely used in the management of what four things?: 1. Gastrointestinal atony
2. Nonobstructive urinary bladder atony
3. Opthalmic disorders (glaucoma)
4. Myasthenia gravis
What are the most common side effects associated with usual therapeautic doses of cholinergic agonists?: Salivation
Lacrimation
Urination
Defecation
Sweating
(SLUDS)
Which direct acting cholinomimetic is characterized by its short duration of action and what is it commonly used for?: Methacholine
Used diagnostically to test for bronchial hyperactivity and asthmatic conditions
Which direct acting cholinomimetic is used to increase tone and contraction of the intestine and urinary bladder?: Bethanechol
Which direct acting cholinomimetics are regarded as being selective for muscarinic receptors?: Methacholine
Bethanechol
Which non-selective direct acting cholinomimetic agent is used in the treatment of glaucoma?: Carbachol
Why is pilocarpine not a substrate for cholinesterases?: It is not a choline ester
What are four contraindications to the use of cholinomimetics?: 1. Asthma
2. Peptic ulcer
3. Coronary insufficiency
4. Hyperthyroidism (causes a-fib)
What are the three groups of cholinesterase inhibitors?: 1. Quaternary alcohols
2. Carbamate esters
3. Organophosphates
Which group of cholinesterase inhibitors is considered irreversible?: Organophosphates
What are three reversible cholinesterase-inhibiting drugs?: Edrophonium
Neostigmine
Physostigmine
What group of cholinesterase inhibitors does edrophonium belong to and what is its use?: Quaternary alcohol
Diagnosis of myasthenia gravis
(reversal of muscles weakness is indicative of condition)
What are the two significant characteristics of neostigmine?: Longer acting
Stays out of the CNS (quaternary amine)
What are the major therapeutic uses for neostigmine?: Nonobtrusive intestinal atony
Nonobtrusive urinary bladder atony
Management of myasthenia gravis
Which reversible cholinesterase inhibitor is sometimes used in the treatment of glaucoma?: Physostigmine
How long does "aging" of AChE bound to organophosphates take?: About 1 hour
What is the only clinical use of organophosphates and which drugs are used?: Glaucoma (as a last resort)
DFP and echothiophate
Does atropine penetrate the CNS?: Only in large doses
Which subtypes of muscarinic receptors does atropine block?: All of them
What is the classic non-muscarinic effect of atropine?: Dilation of blood vessels in facial blush area
Cholinergic blockers are commonly used in the routine management of patients with what? (5): 1. Gastric hypermobility and sapsticity
2. Escessive salivation
3. Need for mydriatic and cyclopegic
4. Cystitis, ureteral or biliary colic
5. Parkinson's Disease
What are the three groups of cholinergic blockers?: Muscarinc blocking drugs
Ganglionic blockers
Nuromuscular blockers
Name three muscarinic blockers.: Atropine
Scopolamine
Ipratropium
What effect does atropine have on NMJs?: None - it is selective for muscarinic receptors
Which pts should not receive topical application of atropine to the eye?: Pts with narrow-angle glaucoma
What is the key difference between scopolamine and atropine?: Scopolamine exerts more CNS action (drowsiness and amnesia)
What is ipratropium used for?: Administered by inhalation in reversible airway disease
What are the therapeutic uses of muscarinic blockers? (6): 1. Before anesthesia
2. To combat motion sickness
3. To manage Parkinson's disease
4. To treat intestinal spasms
5. To prepare the eye for examiniation; to treat iritis
6. To treat poisoning and certain bronchial conditions
What are nondepolarizing ganglionic blockers used for?: Short-term control of blood pressure in HTN crises
What are depolarizing ganglionic blockers used for?: NOTHING!!!!
What is the nondepolarizing ganglionic blocker we need to know?: Trimethaphan camsylate
How is trimethaphan administered and why?: Continuous IV b/c of rapid metabolization by plasma ChE
What is an important side effect of trimethaphan?: Histamine release
Curare, atracurium, cecuronium and mivacurium are in what class of drugs?: Nondepolarizing NMJ Blockers
Compared to curare, atracurium ...: Has shorter duration of action
Has some histamine release
Compared to curare, vecuronium ...: Has shorter duration of action
Does not cause histamine release
Does not cause ganglionic blockade
Compared to curare, mivacurium ...: Has less histamine release
Is very short acting
What is the order in which curare paralyzes skeletal muscles?: Eye muscles
Jaw muscles
Muscles controlling swallowing
Peripheral muscles
Abdominal and intracostal muscles
Diaphragm
Potential complications of curare are what?: Hypotension
Bronchoconstriction
What drugs antagonize curare?: Neostigmine
Edrophonium
What type of drug is succinylcholine?: Depolarizing NMJ Blocker
How long does skeletal muscle paralysis persist following IV injection of succinylcholine?: 5 minutes
How is succinylcholine metabolized?: By plasma pseudo-ChE
What are therapeutic uses of β1 adrenergic receptor antagonists? (11): 1. Ventricular and supraventricular arrhythmias
2. Angina pectoris
3. HTN
4. Cardiac myopathies
5. Long-term prophylaxis after MI
6. Prophylaxis of migraine
7. Hyperthyroidism
8. Glaucoma
9. Management of pheochromocytoma
10. Acute freight/stress syndromes
11. Skeletal muscle tremors
What are therapeutic uses of α-adrenergic receptor antagonists? (8): 1. Essential HTN
2. HTN crises
3. Vasopastic conditions
4. Frostbite
5. Therapeutic management of pheochromocytoma
6. Circulatory shock
7. Congestive heart failure
8. Urinary obstruction (BPH)
What effect does propanolol have on blood pressure?: Initially it raises it, but given chronically it will lower it, especially in pts w/ HTN
Which has a longer half life, metoprolol or atenolol?: Atenolol
Which β1 selective blocker has a very short duration of action?: Esmolol
What is the clnical use of labetalol?: It is a potent antihypertensive
What undesireable effect of non-selective α receptor antagonists severly limits their clinical use?: Tachycardia
(also cause postural hypotension)

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Number of cards 73