Cholinergic Agonists and Antagonists Flashcards
In most organs, which mAChR receptor predominants?
Which predominates in the heart?
Which in smooth muscle?
1) M3
2) M2
3) M3, M2
What are the parasympathetic effects on the iris sphincter muscle?
On the ciliary muscles?
1) Contraction (miosis)
2) Contraction for near vision
What are the parasympathetic effects on the SA node?
What are the parasympathetic effects on the atria?
What are the parasympathetic effects on the AV node?
What are the parasympathetic effects on the ventricles?
1) Decrease HR
2) Decrease in contractile strength and refractory period
3) Decrease in conduction velocity and increase refractory period
4) Decrease in contractile strength
What are the parasympathetic effects on the arteries and veins?
Via what?
Dilation via EDRF
What are the parasympathetic effects on the bronchial muscles?
What are the parasympathetic effects on the bronchial glands?
1) Contraction
2) Stimulation
What are the parasympathetic effects on GI motility?
What are the parasympathetic effects on GI sphincters?
What are the parasympathetic effects on GI secretion?
1) Increase
2) Relax
3) Stimulate
What are the parasympathetic effects on the detrusor muscle?
What are the parasympathetic effects on the Trigone and sphincter?
1) Contraction
2) Relax
What are the parasympathetic effects on the sweat, salivary, lacrimal and nasopharyngeal glands?
Secretion of glands
Accommodative esotropia is a misalignment of the eyes that can be diagnosed and treated with?
Cholinomimetic agonists
What is the most widely used choline ester for GI/GU disorders, including postoperative ileus, congenital megacolon, urinary retention, and esophageal reflux?
What must the physician be certain of otherwise the drug may exacerbate the problem and may even cause perforation?
1) Bethanechol
2) No obstruction
Pilocarpine and cevimeline are used to do what?
What condition does it help?
1) Increase salivary secretion
2) Dry mouth from Sjögren’s syndrome
The overdose of what drug causes predictable muscarinic effects such as nausea, vomiting, diarrhea, urinary urgency, salivation, sweating, cutaneous vasodilation, and bronchial constriction?
What antimuscarinic compounds do you use to treat this?
1) Pilocarpine and the choline esters
2) Atropine
Mushrooms of the genus Inocybe can cause?
Muscarinic poisoning
What are the major contraindications to the use of mAChR agonists that are distributed systemically?
1) Asthma
2) Hyperthyroidism
3) Coronary insufficiency
4) Acid-peptic disease
CNS stimulation (convulsions progressing to coma), Skeletal muscle end plate depolarization, Respiratory paralysis, Hypertension, and Cardiac arrhythmias are all acute toxicity effects of?
Nicotinic stimulants
What are the treatments for acute toxicity effects of nicotinic stimulants?
1) Atropine ganglia
2) Parenteral anticonvulsants (diazepam)
What is approved for intraocular use during surgery and causes miosis (reduction in pupil size)?
Acetylcholine
What is administered by inhalation for the diagnosis of bronchial airway hyperreactivity in patients who do not have clinically apparent asthma?
Methacholine
What can be used to treat patients with urinary retention and heartburn?
What type of agonist is it?
1) Bethanechol
2) Selective mAChR agonist
What is a nonspecific cholinergic agonist that is used for the treatment of glaucoma or to produce miosis during surgery or ophthalmic examination?
Carbachol
What is given as an oral tablet used to treat dry mouth (xerostomia) in patients with Sjögren’s syndrome?
It is metabolized via what?
1) Cevimeline
2) P450 pathways
What is approved for xerostomia treatment in patients with Sjögren’s syndrome or head and neck cancer treatment related xerostomia (PO), miosis during ophthalmic procedures (topical), and for glaucoma (topical)?
What type of agonist is it?
1) Pilocarpine
2) mAChR agonist
Bethanechol may produce urinary tract infection if?
Sphincter fails to relax
What is FDA approved for smoking cessation?
Varenicline
Varenicline is a partial agonist that binds with high affinity and selectivity to what receptor located in the brain to stimulate receptor-mediated activity?
α4β2 nicotinic acetylcholine receptors
Varenicline causes a sustained release of what NT to reduce craving and withdrawal symptoms associated with smoking cessation?
Dopamine
What is the most common adverse effect of Varenicline?
What are some serious adverse effects?
1) Nausea
2) Changes in behavior, agitation, depressed mood,
and suicide
Acetylcholinesterase (AChE) inhibitors such as Alcohols and Carbamic acid esters have what type of charge?
What type of binding does it have to AChE?
Which is more longer lasting?
1) Positive or neutral charge
2) Noncovalent and reversible
3) Carbamic acid esters
What makes AChE inhibitors such as Organophosphates toxic to the CNS?
What type of binding does it have to AChE?
1) Neutral charge and highly lipid-soluble
2) Covalent and irreversible
What category of AChE inhibitors such as neostigmine, pyridostigmine, edrophonium, echothiophate, ambenonium are poorly absorbed?
What category of AChE inhibitors such as physostigmine, donepezil, tacrine, rivastigmine, galantamine are well-absorbed?
1) Quaternary and charged AChE inhibitor
2) Tertiary and uncharged AChE inhibitors
What is required in order to reestablish the termination of ACh signaling at the neuromuscular junction?
Regeneration of AChE
What is the mechanism of action for AChE inhibitors?
ACh accumulation throughout the body and activation of nAChRs and mAChRs
What do AChE inhibitors stimulate at autonomic effector organs?
What do AChE inhibitors stimulate at, followed by depression or paralysis, all autonomic ganglia and skeletal muscle?
What do AChE inhibitors stimulate, with occasional subsequent depression, in the CNS?
1) mAChRs
2) nAChRs
3) Cholinergic receptor sites
The eye, respiratory tract, GI tract, and urinary tract are innervated by what receptors?
mAChRs