test 2 Flashcards
Where do direct acting agonist bind?
Directly to cholinergic receptors
What affects do direct acting agonists have on the heart?
Decrease conduction
Brady cardia
What affects do direct acting agonists have on visceral smooth muscle?
Increase motility in the Gi
Increase detrusor muscle tone
Decrease sphincter tone
What affect do direct acting agonist have on the eyes?
Contracts the sphincter of the iris, contraction of the ciliary muscle, decrease ocular pressure (allows for accomodation)
What affects do direct acting agonists have on exocrine glands?
Increase in SLUDD
Sweat
Lacrimation
Urination
Digestion
Diarrhea
What is acetylcholine used for?
It is a direct acting agonist used for ophthalmology
What is methacholine used for?
Test bronchial hyper reactivity (Bronchiolar constriction of direct acting agonist)
Has muscarinic selectivity
What is carbachol used for?
Direct acting agonist used for opthalmology
Has increased stability
What is bethanechol (urecholine) used for?
Bladder and GI Hypotonia
Direct acting agonist that is more stable and has muscarinic selectivity
What is pilocarpine used for?
Glaucoma and xerostomia it is a muscarinic selective direct acting agonist
What is cevimeline used for?
Xerostomia
Sojourn’s Syndrome
Selective on the M3 receptor direct acting agonist
What is the treatment for toxicity of cholinomimetic compounds?
Atropine (or other muscarinic receptor antagonist)
How do indirecting acting Cholinomimetics work?
They are cholinesterase inhibitors (increase amounts of ACH in the synaptic terminal)
What is the main difference in responses between direct acting and indirect acting cholinomimetics?
Indirect acting has the addition of nicotinic responses (muscle and CNS)
What are the main therapeutic targets of AChE inhibitors?
Skeletal muscle
Central nervous system for Alzheimers
Decrease intraocular pressure of the eye
SLUDD
What is the role of edrophonium?
To diagnose myasthenia gravis but it is a simple alcohol so too short acting so we do not use anymore
What are carbamate esters also called?
Medium acting anticholinesterases
Sometimes called suicide inhibitors (parent compounds are cleaved by enzyme)
What kind of AChEI is neostigmine?
Reversible medium acting anticholinesterase (carbamate ester)
What does neostigmine do?
Prostigmin or neostigmine is used to reverse competitive neuromuscular block that happens during myasthenia gravis
What is pyridostigmine used for?
Mestinon
Used for myasthenia gravis (better absorption and duration of action than neostigmine)
What is physostigmine used for?
Used in eye drops for treatment of glaucoma
What is the most common type of irreversible dementia?
Alzheimer’s disease
What is the most common type of reversible dementia?
Delirium
What is the most common drug associated with delirium that has anticholinergic activity?
Diphenhydramine
What enzyme is lost in alzhiemers disease?
Choline Acetyltransferase (makes ach)
What are the two forms of acetylcholinesterases?
AChE (CNS) and BuChE (plasma)
What kind of drug is Donepezil (Aricept)
Reversible and noncompetitive inhibitor of AChE
(less adverse effects due to high selectivity)
Alzheimers
How is Aricept metabolized?
Liver and kidney
What kind of drug is Rivastigmine (Exelon)
Carbamate Acetylcholinesterase Inhibitor
Active at both AChE and BuChE
Alzheimers
What kind of drug is galantamine (razadyne)
Competitive and reversible AChE inhibitor
Allosterically modulates nAChR
Alzheimers long term
What is the main problem with taking Alzheimers drugs long term?
May exacerbate behavioral problems with long term use
What is the mechanism for organophosphate inhibition of AChE
Form a covalent bond between the phosphate and hydroxyl group of the active site serine
What is isoflurophate?
DFP
Dyflos
Long acting anticholinesterase (organophosphate)
Sarin
What is echothiophate?
Phospholine
Used as eye drops for glaucoma
Organophosphate has a quat amine
What are the signs and symptoms of organophosphate exposure/ due to the muscarinic receptors?
Vomiting
Bronchospasm
Hypotension
Bradycardia
SLUD
Overstimulation of the muscarinic acetylcholine receptors in the parasympathetic system
What are the signs and symptoms of organophosphate exposure due to overstimulation of muscle nicotinic receptors at the NMJ?
Muscle weakness
Fasciculations
Paralysis
What are the signs and symptoms of organophosphate exposure due to overstimulation of nicotinic and muscarinic receptors in the CNS?
Confusion
Agitation
respiratory failure
Coma
What kind of drugs can reverse overstimulation of the Parasympathetic system?
Oximes
2Pam
Obidoxime
HI6
What is the primary cause of death with AChEIs?
Failure of the muscles of respiration
Why is the treatment of organophosphates long term?
They are lipophilic in nature
What is glaucoma associated with?
Ocular hypertension
What can untreated glaucoma lead to?
permanent damage of the optic nerve and resultant visual field loss and blindness