Term
| What enzyme makes Ach? What are the substrates? |
|
Definition
| CAT (choline acetyltransferase) via acetyl CoA and choline |
|
|
Term
| How does ACh get into vesciles? |
|
Definition
| transported via a proton antiporter= VAT |
|
|
Term
| What are the two sites of AchE? |
|
Definition
| anion spot that binds to N+, and active site with serine 203 |
|
|
Term
| What part of Ach is metabolized? |
|
Definition
|
|
Term
| What drug inhibits uptake of choline by the presynaptic neuron? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| How does botulinum toxin work? |
|
Definition
| prevents exocytosis of Ach |
|
|
Term
| What is the mechanism of black widow spider venom? |
|
Definition
| has alpha-latrotoxin which causes release of Ach |
|
|
Term
| Where are M1 receptors found? |
|
Definition
| neuronal CNS and ANS presynaptic |
|
|
Term
| What are the direct acting cholinomimetic drugs? |
|
Definition
| receptor agonists= choline esters, alkaloids |
|
|
Term
| What are indirect acting cholinomimetic drugs? |
|
Definition
| cholinesterase inhibitors= carbamates and organophophates |
|
|
Term
|
Definition
| bethanechol and carbachol |
|
|
Term
| What is the clnical use of ACh? |
|
Definition
|
|
Term
| What type of drug is bethanechol? |
|
Definition
|
|
Term
| What is bethanechol used for? |
|
Definition
| effects mostly on GI and urinary system when asdministered p.o. or S.c. and used to prevent urinary retention after surgery |
|
|
Term
| What type of drug is carbachol? |
|
Definition
| muscarinic and nicotinic agonist |
|
|
Term
| What is carbachol used for? |
|
Definition
| muscarinic and nicotinic agonist |
|
|
Term
| What is carbachol used for? |
|
Definition
| used to produce miosis during ocular surgery |
|
|
Term
| Name some muscarinic alkaloids? |
|
Definition
| muscarine, pilocarpine, and (synthetic) cevimeline |
|
|
Term
| What type of drug is pilocarpine? |
|
Definition
|
|
Term
| What is pilocarpine used for clinically? |
|
Definition
| topically to treat glaucoma, orally for the treatment of zerostomia (Sjorgren's syndrome), somewhat selective for salivary glands |
|
|
Term
| What type of drug is cevimeline? |
|
Definition
|
|
Term
| What is cevimeline used for? |
|
Definition
|
|
Term
| What is closed (or narrow angle) glaucoma? |
|
Definition
| drainage angle of the eye becomes physically blocked by a narrow angle preventing drainage of aqueous humour slowly or suddenly |
|
|
Term
| What is chronic open-angle glaucoma? |
|
Definition
| the drainage angle of the eye becomes less efficient with time causing inefficient drainage of aqueous humour and increased pressure within the eye. Gradually produced optic nerve damage |
|
|
Term
| What is the MC type of glaucoma? |
|
Definition
|
|
Term
| Is closed angle glaucoma acute or chronic? |
|
Definition
|
|
Term
| What are the effects of PNS on the eye? |
|
Definition
M3 contraction of iris sphincter muscle produces miosis
M3 contraction of the ciliary muscle allows near vision |
|
|
Term
| What is the effect of SNS on the eye? |
|
Definition
alpha 1 contraction of iris dilator (radial) muscle causes mydriasis
beta 2 relaxation of ciliary msucle allows you to see far away |
|
|
Term
| What effect does the ANS have on the ciliary epithelium? |
|
Definition
| alpha2 and beta 2 mediates aqueous humor production |
|
|
Term
| What are the glaucoma treatments that increase outflow of aqueous humour? |
|
Definition
mitotic agents (aprasympathomimetics; e.g. pilocarpine)
cholinesterase inhibitors (physostigmine)
prostaglandin analogs (Iatanopros, bimatoprost) |
|
|
Term
| What drugs treat glaucoma by decreasing ciliary body production of aqueous humour? |
|
Definition
| carbonic anhydrase inhibitors (acetazolamide); topical beta-blockers (timolol, levobunolol) |
|
|
Term
| What are the two types of antimuscarinic drugs? |
|
Definition
| natural alkaloids and semi-synthetic derivatives |
|
|
Term
| Name two natural antimuscarinicalkaloids? |
|
Definition
|
|
Term
| Name semi-synthetic derivatives that are antimuscarinic drugs. |
|
Definition
| ipratropium (quaternary), tiotropium (quaternary; 24h duration); glycopyrrolate; oxybutynin |
|
|
Term
| What are the clinical uses of the belladonna alkaloids? |
|
Definition
| preop to reduce salivations/bronchial secretions, reduce intestinal motility, prevent vagal stimulation during anesthesia and surgery, treat overactive bladder, opthalmological examinations, prevent motion sickness, treat asthma, treat AChE inhibitor poisoning |
|
|
Term
| What are the toxic effects of atropine or other muscarinic antagonists? |
|
Definition
| dry, hot, red, blind, mad |
|
|
Term
| What effect does .5mg of atropine have? |
|
Definition
| paradoxical bradycardia; some dry mouth; inhibition of sweating |
|
|
Term
|
Definition
| increased xerostomia; thirst; mild tachycardia; mild mydriasis |
|
|
Term
| What are the effects of >10 mg of atropine? |
|
Definition
| rapid and weak pulse; fixed, maximally dilated pupils; blurred vision; ataxia; excitement; hallucinations and delirium; coma |
|
|
Term
| What is the antidote for atropine overdose? |
|
Definition
| physostigmine (by inhibiting cholinesterase) |
|
|
Term
| What are the three general categories of AChE inhibitors? |
|
Definition
| short acting (non-covalent), medium-duration ('reversible carbamates'); long-duration (irreversible organophosphates) |
|
|
Term
| How do carbamates inhibit cholinesterase? |
|
Definition
| bind to the esteratic site of AChE |
|
|
Term
| Which carbamates penetrate the CNS? |
|
Definition
| physostigmine (neostigmine and pyridostigmine do NOT) |
|
|
Term
| What is physostigmine used for? |
|
Definition
| drug of choice to treat poisoning with atropinic agents; used to treat alzheimer's and dementia |
|
|
Term
|
Definition
| physostigmine, neostigmine, pyridostigmine |
|
|
Term
| What is neostigmine used to treat? |
|
Definition
| myasthenia gravis, antidote for OD of curare-like drugs, treat glaucoma |
|
|
Term
| What is pyridostigmine used to treat? |
|
Definition
| myasthenia gravis, glaucoma |
|
|
Term
| Name a short acting (noncovalent) cholinesterase inhibitor? |
|
Definition
|
|
Term
| What is edrophonium used for? |
|
Definition
| very short acting diagnostic agent used to test for myasthenia gravis |
|
|
Term
| Which cholinesterase inhibitors bind to the active 'esteratic' site versus the choline 'anionic' site? |
|
Definition
| choline 'anionic' site= edrophonium; active 'esteratic' site= physostigmine, neostigmine, pyridostigmine |
|
|
Term
| What is cholinesterase inhibitor acute toxicity termed? |
|
Definition
|
|
Term
| What are the symptoms of cholinergic toxidrome? |
|
Definition
M= salivation, lacrimation, urination, defecation, emesis (vomiting), bradycardia, bronchoconstriction, nausea, mental confusion, seizures
N= fasciculation, muscle cramps, weakness and paralysis of respiratory muscles |
|
|
Term
| What are potential nicotinic receptor effects of high dose AChE inhibitor poisoning? |
|
Definition
| Mydriasis, tachycardia, weakness, hypertension, fasciculations |
|
|
Term
| What is the antidote for OD of carbamate cholinesterase inhibitors? |
|
Definition
|
|
Term
| How do organophosphates inhibit acetylcholinesterase? |
|
Definition
| irreversibly phosphorylate serine hydroxyl at active site of AChE |
|
|
Term
| What are organophophates used for? |
|
Definition
| insecticides (malathion, parathion, diazinon), nerve gases (Sarin, soman, tabun) |
|
|
Term
| How do you treat cholinergic toxidrome? |
|
Definition
| atropine, 2 pralidoxime (2-PAM), Diazepam |
|
|
Term
| What are ganglionic blocking agents and their uses? |
|
Definition
| trimethaphan (produces controlled hypotension), hexamethonium |
|
|
Term
| What are ganglionic stimulating agents? |
|
Definition
| nicotine, and Varenicline (chantix)=partial agonist |
|
|
Term
| What are NMJ blocking agents used for? |
|
Definition
| intubation, maintain controlled ventilation, paralysis of skeletal muscle in area of surgery |
|
|
Term
| What are the two main categories of NMJ blocking drugs? |
|
Definition
| nondepolarizing (competative) versus depolarizing (non-competative) |
|
|
Term
| What are the different types of nondepolarizing (competative) NMJ blocking drugs? |
|
Definition
| long duration (tubocurarine), intermediate duration (pancuronium), short duration (mivacurium) |
|
|
Term
| Name a non-competative (depolarizing) NMJ blocking agent. |
|
Definition
|
|
Term
| What is the effect of depolarizing (noncompetitive) NMJ blocking agents? |
|
Definition
| phase I= contraction (for a few minutes) phase II= relaxed |
|
|
Term
| What is the antidote to NMJ blocking agents? |
|
Definition
| nondepolarizing use neostigmine; for depolarizing (succinylcholine) DON"T USE A DRUG, just ventilate until effects wear off in a few minutes |
|
|
Term
| What are curare-like drugs? |
|
Definition
| nondepolarizing (comopetative) NMJ blocking drugs |
|
|
Term
| In susceptible patients, succinylcholine may produce what side effects? |
|
Definition
| hyperkalemia or malignant hyperthermia |
|
|
Term
| What causes Succinylcholine to wear off in a few minutes? |
|
Definition
| metabolized by butyrlcholinesterases |
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