Cholinergic Agonists and Antagonists Flashcards
Muscarinic Receptors
GPCR receptors M1,M2,M3
M1 Receptors
Increases IP3, DAG and therefore Calcium
Activated myenteric plexus for GI motility and secretions
M2 Receptors
Open potassium channels to decrease heart rate and contractility
Decrease cAMP and Calcium at sympathetic nerves to decrease NE release
M3
Increase Ip3, DAG and calcium
Contract ciliary muscles for accomodation and AH drain
Contract GI, bladder and bronchiolar muscle
Secretions at GI, sweat, tear, salivary glands
Nicotinic Receptors
Ligand gated ion channels
Pentameric structures that open upon ACH binding and cause flow into the cell to initiate downstream effects
Nn
Postganglionic sympathetic and parasympathetic cells
Nm
Neuromuscular junction
Direct Acting Nicotinic
Nicotinic- nicotine, succinylcholine
Competitive Muscarinic Antagonists
Atropine, Scopalamine, Glycopyrrolate
Organophosphate Poisoning
SLUDGE or DUMBBELS
Treat with 2-PAM
SLUDGE and DUMBBELS
Sweating, LAcrimation, Urination, Diarrhea, Gastric Distress, Emesis
Diarrhea, Urination, Miosis, Bronchorrea, Bradycardia, Emesis, Lacrimation, Salivation
Atropine Poisoning
Blind as a bat (dilated, blurred vision) Mad as a hatter (Nervous, confused, hallucinate) Red as a beet (Flushed skin) Hot as a hare (hot skin) Dry as a bone (dry mouth, skin) Bowel and bladder lose their tone And the heart runs alone (tachycardia) Treat with physostigmine, lavage, lower temp, cathertization, barbituates
Nicotine
Activates neuronal nictoinic receptors and is used clinically to help with smoking cessation
Sucinylcholine
Depolarizing block of Nm receptors
Eliminated by butyryl cholinesterase
Used as a neuromuscular block during shock therapy or emergency intubation
Acetylcholine
Quartenary Nitrogen Analog
RAPID half life and is a nicotinic/muscarinic agonst
Eliminated by acetylcholinesterase
No therapeutic use
Metacholine
Quarenary Nitrogen Analog
Slective for muscarinic receptors and is used to diagnose asthma/test for severity
Carbachol
Quartenary Nitrogen Analog
Muscarinic and Nicotinic Agonist
Long half life
Miotic agent in ocular surgery to reduce pressure
Bethanechol
Quartenary Nitrogen Analog
Muscarinic selectivity and a long half life
Urinary retention, bladder atony
Pilocarpine
Tertiary Amine
1 hour half life, selective for musarinic receptor
Treats dry mouth from radiation or sjorgens
Treat narrow angle glaucoma
Neostigmine
Reversible AChE inhibitor with a mid half life
Treats muscle weakness from myasthenia gravis
REverse neuromuscular block
Edrophonium
REversible AChE inhibitor with a short 10 min half life
USed to diagnose muscle weakness from disease or too much neostigmine
Physostigmine
Reversible AChE inhibitor with a longer half life
Treats delirium from anticholinergic drugs (Atropine)
TReats glaucoma
Donepezil
Reversible AChE inhibitor to treat alzheimers
Pralidoxime (2-PAM)
Reverse organophosphate poisoning with a 75 min half life by being a peripheral AChE REactivator
Echothiophate
Irreversible AChE inhibitor (LONG half life)
Treats open angle glaucoma
Atropine
Muscarinic antagonist Treats: - excessive secretions in surgery - high frequency/urgency of peeing - cystitis association - hypertonic gut - organophosphate poisoning - bradycardia
Scopolamine
Muscarininc antagonist to treat motion sickness and as an anti-saligogue (salivay secretion) during surgery
Glycopyrrolate
Muscarinic receptor antagonist that is used to protect agains excessive muscarinic activation during the reversal of neuro-muscular blockade during surgery, anti-saligogue
Quartenary N Analog Muscarinic Agonists
ACH, methachoine, carbachol, bethanechol
Tertiary Amine Muscarinic Agonists
Muscarine, Pilocarpine
Cholinesterase Inhibitors
Neostigmine, edrophonium, physostigmine, donepezil
Irreversible cholinesterase inhibitors
organophosphates (reverse with 2PAM), echothiophate
Muscarinic Antagonists
Atropine, Scopolamine, Glycopyrrolate
