Parasympathetic Activation / Cholinomimetic Agents

Question 1

4 CNs involved in parasympathetic NS

Answer 1

1. CN III
2. CN VII
3. CN IX
4. CN X

Question 2

All preganglionic neurons use what NT and act on what receptor

Answer 2

ACh; act on nicotinic receptors

Question 3

What is unique about parasympathetic preganglonics?

Answer 3

Ae very long and synapse in ganglia near target organs; this makes their actions more localized

Question 4

Parasympathetic postganglionic neurons use what NT and what receptor

Answer 4

ACh–> on muscarinic receptors

Question 5

What is the difference in nicotinic and muscarinic receptors in terms of how they produce their effects

Answer 5

Nicotinic–> open ligand gated Na/K channels

Muscarinic–> activate GPCRs and effect 2nd messenger systems

Question 6

Other than autonomic ganglia, where else in the body are nicotinic receptors found?

Answer 6

1. at the NMJ; part of somatic nervous system

2. adrenal medulla (sympathetic NS)

Question 7

Other than CNs, where else are parasympathetic nerves found?

Answer 7

2nd and 3rd SACRAL spinal nerves (hence name craniosacral system)

Question 8

parasympathetic action in GI

Answer 8

increased motility and tone–> increased digestion

Question 9

parasympathetic action in bladder

Answer 9

relaxes sphincter, increases muscle tone of bladder wall

Question 10

Parasym NS action in eye

Answer 10

1. miosis

2. ciliary muscle contraction (accomodation)

Question 11

Parasym NS action on lung

Answer 11

Contraction–> increased bronchial tone

Question 12

Parasymp NS action on heart

Answer 12

decreased HR; some decrease in contractility

Question 13

parasymp activity in lacrimal glands

Answer 13

stimulate tears

Question 14

parasymp activity in salivary gland

Answer 14

watery secretion

Question 15

parasymp effect on g.u.

Answer 15

erection (of penis or clitoris)

Question 16

mnemonic for orhanophosphate poisoning/ cholinergic excess

Answer 16

DUMBELSS

Not specific for only parasympathetic action; nicotinic and muscarinic receptors are found elsewhere too

Question 17

what does DUMBELSS stand for

Answer 17

1. diarrhea
2. urination
3. miosis
4. bronchospasm
5. excitation of muscle/CNS (nicotinic @ NMJ)
6. lacrimation
7. salivation
8. sweating

Question 18

other than parasympathetic post ganglionic nerve targets, where else in body are muscarinic receptors found

Answer 18

Sweat glands

Question 19

organophosphate mechanism of injury

Answer 19

inactivates acetylcholineesterase–> ACh excess–> excess cholinergic stimulation

Question 20

What two drugs are given for cholinergic excess/ organophosphate toxicity

Answer 20

1. Atropine–> (blocks muscarinic rceptors)

2. Pralidoxime–> (regenerates acetylcholinesterase

Question 21

ptosis and diplopia that worsens throughout the day

Answer 21

Myasthenia gravis

Question 22

what drug is used to test for myasthenia gravis

Answer 22

edrophonium (Tensilon test)

Question 23

50% M.G. asociated with thymic ______

Answer 23

hyperplasia

Question 24

20% M.G. associated with thymic _____

Answer 24

atrophy

Question 25

15% M.G. associated with thymic ________

Answer 25

tumor (thymoma)

Question 26

What causes a Myasthenia crisis (symptom)

Answer 26

Rapidly progressing weakness in respiratory muscles

Question 27

4 treatments for myasthenia gravis

Answer 27

1. immunotherapy (cyclosporine, immunotherapy) 2. Plasmapheresis 3. Indirect cholinergic agent 4. thymectomy

Question 28

3 anticholinesterases useful for tx of Alzheimer's

Answer 28

1. Donepezil 2. Galantamine 3. Rivastigmine

Question 29

who gets poisoned by organophosphates

Answer 29

farmers

Question 30

4 direct cholinomimetic agonists

Answer 30

1. Bethanecol 2. Carbachol 3. Pilocarpine 4. Methacholine

Question 31

direct ACh agonist given for postoperative ileus, neurogenic ileus or urinary retention

Answer 31

Bethanecol

Question 32

direct ACh agonist given for glaucoma

Answer 32

Carbachol

Question 33

agonist that is an analoque of ACh

Answer 33

Carbachol

Question 34

agonist that is potent stimulator of sweat, tears, and saliva; given for glaucoma (both open and closed)

Answer 34

Pilocarpine *cry, drool, sweat on your PILOw"

Question 35

direct agonist given as challenge test for asthma

Answer 35

Methacholine *stimulates muscarinic receptor in lung to induce bronchspasm

Question 36

5 indirect agents (anticholinesterases)

Answer 36

1. Neostigmine 2. Pyridostigmine 3. Edrophomium 4. Physostigmine 5. Donepezil

Question 37

indirect agent for short term tx of myasthenia gravis

Answer 37

Neostigmine

Question 38

indirect agent that reverses non-depolarizing NMJ blockers

Answer 38

Neostigmine

Question 39

indirect agent used for long term tx of myasthenia gravis

Answer 39

Pyridostigmine

Question 40

which indirect agent can cross the BBB

Answer 40

Physostigmine

Question 41

With all chlinomimetic agents, exacerbation of what three conditions can occur

Answer 41

1. COPD 2. Asthma 3. Peptic Ulcer Disease

Question 42

indirect agent used for atropine overdose

Answer 42

Physostigmine * "Phyxes" atropin OD