Chapter 7-8 Transcript Flashcards

(101 cards)

1
Q

What is a cholinergic drug?

A

is also referred to as a cholinomimetic or parasympathomimetics

SLUDGE on steroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the two main types of receptors associated with cholinergic drugs?

A
  • Muscarinic
  • Nicotinic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the two classifications of drugs that mimic acetylcholine?

A
  • Direct-acting drugs
  • Indirect-acting drugs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do direct-acting drugs do?

A

They bind to acetylcholine receptors and elicit a response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the function of indirect-acting drugs?

A

They inhibit acetylcholinesterase, increasing acetylcholine in the synapse.

Inhibit the inhibitor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the effects of muscarinic agonism?

A

Parasympathetic (rest and digest) on steroids
*
Increased secretions (saliva, tears, sweat)
* Increased gastrointestinal motility
* Nausea
* Vomiting
* Diarrhea
* Bronchospasm
* Headache
* Visual disturbances

Decrease HR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is atropine used for?

A

Atropine is an anti-muscarinic that can reverse symptoms of muscarinic toxidrome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the key differences between muscarinic and nicotinic receptors?

A
  • Muscarinic receptors are G-protein coupled receptors
  • Nicotinic receptors are ion channels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is muscarine and how is it related to acetylcholine?

A

Muscarine mimics acetylcholine but only binds to muscarinic receptors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where was muscarine first identified?

A

Muscarine was identified from the poisonous mushroom Amanita muscaria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the effect of nicotine on the autonomic nervous system?

A

Nicotine stimulates both sympathetic and parasympathetic systems.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the two types of direct-acting drugs?

A
  • Esters of choline - ach, sux, metacholine
  • Alkaloids- nicotine , betel nut, pilacarpine, lobe line
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are common examples of esters of choline?

A
  • Acetylcholine
  • Methacholine
  • Carbachol

Sux

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the primary use of acetylcholine?

A

Acetylcholine is primarily used for inducing pupillary constriction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the effects of methacholine?

A

Methacholine is used for diagnosing asthma by constricting airways.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the main alkaloids classified as direct-acting?

A
  • Muscarine
  • Nicotine
  • Pilocarpine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does nicotine affect the central nervous system?

A

Nicotine has an alerting reaction within the central nervous system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the role of atropine in relation to muscarinic receptors?

A

Atropine blocks muscarinic receptors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Fill in the blank: The _______ receptor is associated with the neuromuscular junction.

A

nicotinic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

True or False: Muscarinic receptors respond to both acetylcholine and nicotine.

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What happens when nicotinic receptors are activated?

A

They stimulate both sympathetic and parasympathetic systems.

Sympathetic dominates in nicotinic response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the effect of high levels of muscarine in the system?

A

It exaggerates the symptoms of muscarinic agonism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Fill in the blank: The _______ mushroom is known for producing muscarine.

A

Amanita muscaria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What forms is nicotine available in?

A

Nicotine is available as a patch, gum, and in a vape pen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the beetle knot and where does it come from?
The beetle knot is a source of a raccoon and comes from the Sareca plant.
26
What is the primary action of raccoon, similar to nicotine?
Raccoon has an alerting action.
27
Why has the beetle knot been banned in many countries?
It has been banned due to the bright red coloration it leaves on pavements when chewed.
28
Where do nicotinic receptors bind in the body?
Nicotinic receptors bind in the central nervous system and peripheral nervous system.
29
What effect does nicotine have on dopamine transmission?
Nicotine increases the transmission of dopamine in the central nervous system.
30
True or False: Dopamine increase is associated with addiction.
True
31
What is the significance of the blood-brain barrier concerning alkaloids?
Alkaloids are lipid soluble and can readily cross the blood-brain barrier.
32
What is the effect of nicotine on the cardiovascular system?
It reduces peripheral vascular resistance and can decrease blood pressure.
33
What is glaucoma and how is it related to aqueous humor?
Glaucoma occurs due to excess production of aqueous humor, leading to increased pressure on the ocular nerve.
34
What is the role of the canal of Schlemm in the eye?
The canal of Schlemm drains aqueous humor from the eye.
35
Fill in the blank: Atropine is contraindicated in _______ glaucoma.
closed-angle
36
What happens to the pupil when compounds that constrict the pupil are used?
They assist with drainage of aqueous humor and relieve pressure in glaucoma.
37
What is the effect of nicotine on the respiratory system?
It causes contraction of smooth muscle in the bronchial tree and increases bronchial mucosa secretion. Think smokers lungs with nicotine
38
What is the effect of nicotine on gastrointestinal activity?
It increases secretion and activity in the gut.
39
What is the duration of action for succinylcholine?
5 to 15 minutes.
40
What are the three main categories of indirect-acting cholinergic agents?
1. Simple alcohols 2. Carbamates 3. Organophosphates
41
What is the primary function of acetylcholinesterase?
To hydrolyze acetylcholine in the synapse.
42
What is the effect of organophosphates on acetylcholinesterase?
They bind covalently to acetylcholinesterase, leading to prolonged effects.
43
What is the role of pralidoxime in organophosphate exposure?
Pralidoxime can help break the organophosphate from acetylcholinesterase.
44
What can happen if organophosphates age?
Pralidoxime may no longer be effective in treating the exposure. Think the longer they are there the harder they are to treat/remove from achE
45
What are the symptoms of high doses of nicotine?
Tremor, emesis, stimulation of respiratory centers, convulsions, and possibly fatal coma.
46
What is the effect of nicotine on the spinal cord compared to the brain?
The spinal cord has more nicotinic than muscarinic receptors.
47
What can neostigmine be used for?
It can be used for post-operative ileus and myasthenia gravis. Anti cholinergic= treats sludge
48
What is the result of acetylcholine being released repeatedly into the synapse?
It allows for sustained muscle contraction may lead to flaccid paralysis
49
What is the medical emergency associated with closed-angle glaucoma?
Rapid increase in intraocular pressure leading to potential vision loss.
50
What is pralidoxime used for?
It is used to treat organophosphate poisoning by reactivating acetylcholinesterase ## Footnote Pralidoxime is administered alongside atropine to improve efficacy before organophosphate aging occurs.
51
What is the effect of organophosphate poisoning on the central nervous system?
It causes diffuse activation of cholinergic neurons, leading to weakness, convulsions, coma, and death at high doses.
52
What are the major therapeutic uses of acetylcholinesterase inhibitors?
* Diseases of the eye (e.g., glaucoma) * GI and urinary tract disorders - dont give to bph - increased urine - increased urinary retention * Neuromuscular junction disorders (e.g., myasthenia gravis) Reversal of NMB
53
What autoimmune disease is associated with the destruction of acetylcholine receptors?
Myasthenia gravis
54
What is the primary mechanism of action of cholinesterase inhibitors in myasthenia gravis?
They prolong the presence of acetylcholine in the synapse, compensating for fewer receptors.
55
What is edrophonium used for in the context of myasthenia gravis?
It is primarily used for diagnostic purposes to assess muscle strength.
56
What are some examples of acetylcholinesterase inhibitors used therapeutically?
* Neostigmine * Pyridostigmine
57
What is the function of atropine in the treatment of organophosphate poisoning?
It blocks the effects of excess acetylcholine at muscarinic receptors.
58
What symptoms are associated with excessive parasympathetic nervous system activity?
* Salivation * Lacrimation * Urination * Defecation * Gastrointestinal motility * Emesis * Miosis * Bronchial constriction
59
What acronym is used to remember symptoms of parasympathetic toxicity?
SLUDGE BM
60
What is the role of cholinesterase inhibitors in cases of muscarinic mushroom poisoning?
They increase acetylcholine levels to counteract toxic effects.
61
What is the difference between muscarinic and non-muscarinic mushroom poisoning?
* Muscarinic poisoning affects acetylcholine receptors and produces SLUDGE symptoms * Non-muscarinic poisoning can lead to liver and kidney failure without initial symptoms
62
What is the significance of organophosphate aging?
It stabilizes the bond with acetylcholinesterase, making it harder to reactivate the enzyme.
63
What is the mechanism of action of direct-acting nicotinic stimulants?
They activate nicotinic receptors, leading to sympathetic and parasympathetic effects.
64
What are the potential consequences of nicotine ingestion in children?
It can lead to fatal toxicity due to the mistaken identity of cigarettes as candy.
65
In a poisoning case, what initial treatment is indicated for suspected organophosphate exposure?
Atropine and pralidoxime
66
What class of drugs includes atropine and its derivatives?
Anti-muscarinic drugs which are anticholinergic
67
What plant is atropine derived from?
Belladonna (Deadly Nightshade)
68
What historical use did the berries of the Belladonna plant have?
They were used to dilate pupils for cosmetic purposes.
69
What is the effect of acetylcholine on the pupil?
Constricts the pupil ## Footnote Acetylcholine causes meiosis, or constriction of the pupil.
70
What is the name derived from the plant Belladonna?
Bella Donna means beautiful woman ## Footnote The dilation of the pupil is thought to signal beauty or sexual readiness.
71
Which isomer of the Belladonna plant is stronger?
L-isomer ## Footnote The L-isomer is much stronger than the D-isomer.
72
What is atropine's role in relation to acetylcholine?
Atropine is a competitive inhibitor of muscarinic receptors ## Footnote It blocks the effects of acetylcholine, requiring more agonist to achieve the same effect.
73
What is the primary use of atropine and scopolamine?
Ophthalmic procedures ## Footnote They are used to dilate the pupil for eye exams and surgeries. Also treatment for sludge - cholinergic (parasympathetic) effects
74
What is the effect of atropine on the airways?
Dilates the airways ## Footnote Atropine counteracts the constricting effect of acetylcholine.
75
What condition might benefit from atropine due to its bronchodilating effects?
COPD ## Footnote Atropine is more useful for COPD than for mild asthma.
76
What is the effect of atropine on gastrointestinal and genitourinary movement?
Slows down movement ## Footnote Atropine can be used to manage excessive GI and GU activity.
77
What is the duration of action for tropicamide?
About six hours ## Footnote Tropicamide is preferred for routine eye exams due to its shorter duration. Atropine can last 7-10 days
78
At low doses, what initial effect does atropine have on heart rate?
Induces bradycardia ## Footnote Atropine initially slows the heart rate before increasing it at higher doses.
79
What is the anticholinergic toxidrome characterized by?
Dry as a bone, red as a beet, blind as a bat, mad as a hatter ## Footnote These symptoms result from excess atropine leading to decreased secretions and central nervous system effects.
80
What is scopolamine primarily used for?
Motion sickness ## Footnote Scopolamine is effective when delivered via a patch behind the ear.
81
What happens to urinary output when atropine is administered?
Decreases urination ## Footnote Atropine can exacerbate urinary retention, especially in males with prostate issues.
82
Which drug class does hexamethonium belong to?
Ganglion blocking agents ## Footnote Hexamethonium is no longer in use due to its lack of specificity.
83
What are neuromuscular junction blockers used for?
Muscle relaxation ## Footnote They block nicotinic receptors at the neuromuscular end plate.
84
What is a common side effect of succinylcholine?
Hyperkalemia ## Footnote Excess potassium in the bloodstream can occur with prolonged use. Muscle soreness
85
What distinguishes depolarizing muscle relaxants from non-depolarizing ones?
Depolarizing agents initially activate the receptor, while non-depolarizing agents block it ## Footnote Depolarizing agents lead to initial contraction followed by paralysis.
86
What is the effect of botulinum toxin?
Inhibits acetylcholine release by cleaving snare proteins preventing vesicle from fusing at NMJ ## Footnote Botulinum toxin is not useful for lowering blood pressure.
87
What is the role pseudocholinesterase in relation to succinylcholine?
Breaks down succinylcholine in the plasma ## Footnote This allows succinylcholine to have a short duration of action.
88
What is the primary action of acetylcholine?
Acetylcholine depolarizes the cell ## Footnote Acetylcholine has a short half-life and is quickly broken down.
89
What happens to the cell after acetylcholine is broken down?
The cell repolarizes ## Footnote This repolarization is necessary for the cell to return to its resting state.
90
What are fasciculations?
Initial contractions caused by depolarization ## Footnote These contractions occur before flaccid paralysis sets in.
91
What is the difference between phase one and phase two block?
Phase one block allows for initial contraction; phase two block renders cells unresponsive to acetylcholine ## Footnote Phase two is not ideal for muscle relaxation and may require artificial ventilation.
92
What is the main use of depolarizing muscle relaxants like succinylcholine?
Facilitating intubation and rapid skeletal muscle relaxation ## Footnote These are used in emergency situations where quick muscle relaxation is essential.
93
What are potential side effects of succinylcholine?
Fasciculation, muscle pain, hyperkalemia, malignant hyperthermia ## Footnote Hyperkalemia can cause serious complications, especially in certain individuals.
94
What are non-depolarizing muscle relaxants?
Competitive antagonists that block acetylcholine receptors without depolarizing the end plate ## Footnote Examples include rocuronium and vecuronium.
95
What is sugamidex used for?
Rapid reversal of certain non-depolarizing muscle relaxants like rocuronium ## Footnote Sugamidex encapsulates the drug, preventing it from binding to receptors.
96
What is the mechanism of action of sugamidex?
It surrounds the rocuronium molecule, preventing it from binding to acetylcholine receptors ## Footnote This allows for quick recovery from neuromuscular blockade.
97
How can neuromuscular blockade be monitored?
Using the train of four method ## Footnote This involves applying electrical impulses to the muscle and measuring the contractions.
98
What is the ideal state of neuromuscular block for intubation?
Phase one block ## Footnote This state allows for effective muscle relaxation without the complications of phase two block.
99
What is the role of neostigmine?
It can reverse the effects of non-depolarizing muscle relaxants ## Footnote Neostigmine works by inhibiting acetylcholinesterase, increasing acetylcholine availability.
100
True or False: Succinylcholine has a long duration of action.
False ## Footnote Succinylcholine has a very short duration of action.
101
Fill in the blank: Excessive activation of skeletal muscle can lead to _______.
malignant hyperthermia ## Footnote This is particularly concerning for patients with specific genetic defects.