ANS Flashcards
What does muscarinic stimulation in sphincter muscle of the iris of the eye cause?
Miosis
What does muscarinic stimulation in arterioles cause?
Vasodilation
What does muscarinic stimulation in heart cause?
Negative chronotropic and inotropic respnses
What does muscarinic stimulation in bronchial smooth muscle cause?
Bronchoconstriction
What does muscarinic stimulation in GI and GU systems cause?
Salivation
Lacrimation
Urination
Diarrhea
What kind of stimulation of the heart causes +inotropic and +chronotropic response?
Beta 1
What kind of stimulation of the bronchus causes bronchodilation?
Beta 2
What kind of stimulation of the myometrium causes relaxation?
Beta 2
What kind of stimulation of the pancreas causes insulin release?
Beta 2
What kind of stimulation of arterioles causes vasoconstriction?
Alpha 1
What kind of stimulation of radial muscles of the iris causes mydriasis?
Alpha 1
What kind of stimulation reduces norepinephrine release?
Alpha 2
What are the two types of parasympathomimetics?
Muscarinic agonists
Cholinesterase inhibitors
What is the one type of parasympatholytic?
Muscarinic antagonist
Acetylcholine: Category?
ANS - parasympathomimetic
Acetylcholine: MOA?
Muscarinic and nicotinic agonist
Acetylcholine: Distinguishing characteristics?
Rapidly hydrolyzed by esterases
Acts on musc. and nic. receptors
Quaternary ammonium group invokes polarity
Acetylcholine: Predictable characteristics?
Short half life (seconds)
Diffuse activity
Limited distribution
Acetylcholine: Predictable uses?
Local ophthalmic use (but better products available)
Bethanechol (Urecholine): Category?
ANS - parasympathomimetic
Bethanechol (Urecholine): MOA?
Muscarinic agonist
Bethanechol (Urecholine): Distinguishing characteristics?
Not metabolized by esterase enzymes
Quaternary ammonium compound
Particular affinity for gut and bladder smooth muscle
Oral route preferred
Bethanechol (Urecholine): Predictable characteristics?
No CNS effect
T1/2 allows dist. to areas of low blood flow
Bethanechol (Urecholine): Predictables uses?
Postoperative gastroparesis
Urinary retention
Xerostomia
Ocular diagnostics
Bethanechol (Urecholine): Predictable side effects?
Other parasympathomimetic effects especially following parenteral Rx
Neostigmine: Category?
ANS - Parasympathomimetic
Neostigmine: MOA?
Reversible cholinesterase inhibitor
Neostigmine: Distinctive characteristics?
Quaternary ammonium compound
Contains ester group- slowly hydrolyzed
Poorly absorbed following oral Rx
Neostigmine: Predictable activities?
Elevates Ach levels
Causes both muscarinic and nicotinic stimulation
Numerous peripheral side effects but not CNS
Neostigmine: Predictable uses?
Miosis and Rx glaucoma (local)
Rx myasthenia gravis
Antidote to some drugs (atropine)
Atonic gut and bladder
Malathione: Category?
ANS- Parasympathomimetic
Malathione: MOA?
Irreversible cholinesterase inhibitor
Malathione: Distinguishing characteristics?
Tertiary ammonium compound
Binds covalently to esterase enzymes
Not hydrolyzed by esterase enzymes
Rapidly absorbed through multiple routes
Malathione: Predictable characteristics?
Causes SLUD and other ANS activities Causes CNS disturbances No therapeutic use Used as insecticide Similar agent used as chemical weapons Atropine is antidote plus supportive therapy
Atropine: Category?
ANS- parasympatholytic
Atropine: MOA?
Muscarinic receptor antagonist
Atropine: Distinguishing characteristics?
From plant source (atropa belladonna) Tertiary ammonium compound Ester group required for activity Resistant to hydrolysis by esterases Metabolized in liver with t1.2 of ~4hr
Atropine: Predictable activities?
CNS toxicity (especially kids) Inhibit SLUD Used in ophthalmology (mydriasis and cycloplegia) Antidote to parasympathomimetics Used to treat diarrhea
Ipratropium: Category?
Parasympatholytic
Ipratropium: MOA?
Muscarinic antagonist