Exam2Lec4CholinergicPharm Flashcards
Acetylcholine is a _
NT that is released from nerve from presynaptic term to bind to post synaptic receptor
Explain how ACh is made
What are the ACh receptors?
What terminates the ACh signal?
Receptors:
* Nicotinic (Ion channels)
* Muscarinic (GPCR)
Terminates: acetylcholine esterase
What are the choline ester and alkaloid direct acting acetylcholine receptor agonist?
- Choline Ester: acetylcholine, methacholine, bethanechol, carbachol
- Alkaloid: Muscarine, pilocarpine, nicotine
Does the alkaloid class use AChE metabolism
NO
Does nicotine have muscarinic AChR activity?
Does muscarine have nicrotinic AChr activity?
NO and NO
Which one (choline ester or alkaloid) can cross the membrane
- Alkaloid will distrub throughout the body
- Choline ester is charged so it cannot cross the membrane
What are the different muscarinic receptors?
- M1, M3, M5 (odd): Gq-coupled, PLC activation, ↑ DAG & IP3 production, ↑ Ca2+
* mobilizes calcium to cause contraction and glandular secretion - M2, M4 (even): Gi-coupled, ↓ cAMP, ↓ PKA
* inhibits Adlyl cyclase
Where are the muscarinic receptor location
end organs
* cardiac and smooth muscle, gland cells, nerve terminals
* Sweat glands, skeletal muscle arterioles (sympathic)
fill in
What is the mAChr associated with mucosal gland? What is the effect?
M1, incr secretion
What is the inn, type of mAChR and its effect on the heart?
- Inn: para
- mAChR: M2
- Effect: decrease BP and bradycardia
What is the inn, TYPE OF mAChR and effect of the vasc. endothelium
- Inn: none but can be de/activated by agonist or antagonist
- ActionL EDRF/NO release, VSM dilation (M3)
- Effect: decrease BP and reflex tachycardia
What is the inn, action of mAChR and effect of the sweat glands with muscarinic receptors
- Inn: symp
- Action: stimulation (M3)-> sym but ACH
- effect: increase secretion
What is the mechanisms of action and pharmacology?
- Activate muscarinic receptors
– Affect all muscarinic receptor subtypes - Mainly evoke parasympathomimetic effects
- Mild or no desensitization-> IMP BECAUSE NIC DOES DESENS
What does high IOP causes?
How is it caused?
- High IOP causes loss of optic nerve and permanent blindness, open angle glaucoma
- Caused by increase aqu humor
How can we reduce the ocular hypertension?
- Ocular hypertension can be reduced by increasing aqueous humor flow OUT via Canal of Schlemm
- Contraction of cillary muscle (via activation of M3 receptor) opens the Trabecular meshwork and facilitates aqueous humor outflow
What are drug class+ drug name that can be used to treat glaucoma? Which ones cannot and why?
- Alkaloids (uncharged, lipophilic)-> drug name: pilocarpine can be used to treat
- Choline esters (charged)-> drug name Bathanechol cannot be used to treat becasue unable to penetrate to the eye cillary muscle
What is the AE, contradinication and interactions with Bethanechol, methacholine and pilocarpine?
- AD: Parasympatheitic effects, bronchospasms, hypotension (vasodilation), reflex tachycardia, decrease secretion
- Cont: Asthma, COPD, peptic ulcer, hypotension
- Interactions: B-Blockers
What is the drug class and drug name of direct action nicotinic agonists
- Class: alkaloid-> increase bioav (not charged/lipophilic
- Drug name: Nicotine
- Where is the distribution of nicotinic receptors?
- What type of effect will they cause?
- NMJ, Autonomic ganglia, Brain
- Symp and para
All subtypes of Nictonic Receptors are ____ cation channels activated by ____.
Pentameric, ACh
Does nicotinic ACh receptor desensitize?
Yes they can desensitize with prolonged agonist
Explain what happens at the NMJ
Ach binds to cause Na to come in then cause AP and Ca+Na flow in which causes contraction