Autonomic Nervous system and drugs

Question 1

What is the action of Botulinum toxin? What bacteria is it associated with?

Answer 1

Action: Protease that cleaves SNARE proteins –> Inhibits release of ACH –> FLACCID paralysis

Bacteria: Clostridium (other clostridia are C. Diff, Tetanus, and C. Perfringens)

Note: Carried on a phage (Shiga, Botulinum, Cholera, Diptheria, strep pyogenes)

Question 2

What are the pre and post ganglionic receptors for parasympathetic innervation?

Answer 2

Pre: Ach-Nictoninc-(N)
Post: Ach-Muscarinic-(1-5)

Question 3

How do nicotinic acetylcholine receptors work? Where are they found?

Answer 3

Ach-Nicotinic(n) AND Ach-Nicotinic(m) receptors = Na/K channels

Found in:

• Parasympathetic preganglionic (N-n)
• Sympathetic preganglionic (N-n)
• Adrenal medulla (N-n)
• Skeletal muscle (N-m)

Question 4

How do muscarinic acetylcholine receptors work? Where are they found?

Answer 4

muscarinic receptors = GPCR

Found in:

• Parasympathetic postganglionic
• Sympathetic postganglionic (sweat)

Question 5

All preganglionics act on what kind of receptors?

Answer 5

Nicotinic-N acetylcholine

Question 6

Where are Nicotinic-M acetylcholine receptors found?

Answer 6

ONLY in skeletal muscle

Question 7

Where are Muscarinic acetylcholine receptors found?

Answer 7

Postganglionic parasympathetics (all) and sympathetics (sweat)

Question 8

What are the pre and post ganglionic receptors of the sympathetic nervous system?

Answer 8

Pre: Acetylcholine Nicotinic-N (like all preganglionics)

Post:

1. Norepinephrine Alpha and Beta (most places)
2. Acetylcholine Muscarinic (sweat glands)
3. D (renal vessels and renal smooth muscle)
4. nothing postganglionic for adrenal medulla

Question 9

Where are norepinephrine alpha and beta receptors found?

Answer 9

On sympathetically innervated:

• cardiac cells
• smooth muscl
• glands
• nerve terminals

NOT on sweat glands and adrenal medulla (which are also sympathetic). Those have Ach-M (sweat) and Ach-Nn (adrenal medulla)

Question 10

What are the pre and post ganglionic receptors of the adrenal medulla?

Answer 10

Trick question! There is no pre/post. Just one neuron synapsing onto Acetylcholine-Nicotonic-N receptors

Question 11

What are the pre and post ganglionic receptors of the parasympathetic nervous system?

Answer 11

Pre: Acetylcholine-Nictoninic-N

Post: Acetylcholine-Muscarinic

Question 12

What are the pre and post ganglionic receptors of skeletal muscle?

Answer 12

Trick question: There is no pre/post! Just one neuron synapsing onto Acetylcholine-Nicotinic-M receptor (the ONLY place we see nicotinic-M!)

Question 13

What 4 broad categories does the sympathetic nervous system innervate?

Answer 13

1. Sweat glands (use Ach-M receptor)
2. Adrenal medulla (uses Ach-Nn receptor)
3. Renal vasculature, renal SM (uses D receptor)
4. Cardiac, SM, glands (use NE-alpha or NE-beta receptors)

Question 14

First generation antihistaminics (H1 histamine receptor blocks) have what undesirable side effects?

Answer 14

1. Antimuscarinic (Pupillary dilation, dry mouth, urinary retention, constipation)
2. Anti-alpha-adrenergic (hypotension, dizziness)
3. Anti-serotonergic (apetite stim, weight gain)

Question 15

What do alpha 1 receptors do?

Answer 15

1. Vasoconstriction (smooth muscle in the vessels contracts)
2. Intestinal/bladder sphincter contraction
3. Pupillary dilation

*memory: Picture making an alpha with string. You pull it TIGHTER to do vasoconstriction and bladder sphincter constriction, You LOOSEN it to make an eye (pupillary dilation)

Question 16

What do alpha 2 receptors do?

Answer 16

1. Decrease sympathetic outflow - STOP RUNNING
2. Decrease insulin release - STOP TAKING UP SUGARY FOR ENERGY
3. Decrease lipolysis - STOP USING FAT FOR ENERGY
4. Decrease aqueous humor production - DONT WORRY ABOUT GETTING WIND IN YOUR EYES
5. Increase platelet aggregation - NOW THAT YOU ARE DONE RUNNING, HEAL UP

*memory: Everything you would want to do to relax. Time 2 acclimate.

Question 17

What do beta 1 receptors do?

Answer 17

1. Increase HR
2. Increase contractility
3. Increase renin release (vasoconstriction, water retention)
4. Increase lipolysis

*memory: There is 1 Bear behind you

Question 18

What do beta 2 receptors do?

Answer 18

1. Vasodilation - BLOOD FLOW
2. Bronchodilation *“easier 2 Breathe” - BREATHE
3. Decrease uterine tone (tocolysis) - DONT HAVE A BABY
4. Ciliary muscle relaxaiton (increase long range focal distance) - LOOK FAR AWAY
5. Increase lipolysis - BREAK DOWN FAT FOR ENERGY
6. Increase insulin release - TAKE UP GLUCOSE FOR ENERGY
7. Increase aqueous humor production - GET STUFF OUT OF YOUR EYES

*memory: Everything you would want to do if you were running away from something. Time 2 book it.

Question 19

What receptor increases aqueous humor production? Decreases it?

Answer 19

Increase: Beta 2 (memory: Time 2 Book it. Increase production when need to get stuff out of your eyes so you can run)
Decrease: Alpha 2 (memory: Time 2 Accomodate. No need to waster energy worrying about things getting in your eyes).

Question 20

What receptor causes pupillary dilation?

Answer 20

Alpha 1

*memory: loosen an alpha string to make an eye

Question 21

What receptor causes lipolysis?

Answer 21

Beta 1 and Beta 2

*memory: 1 bear behind you, time 2 Book it

Question 22

What receptor decreases lipolysis and insulin release?

Answer 22

Alpha 2 *memory: Time 2 Accomodate; chill out

Question 23

What receptor causes vasodilation? vasocontriction?

Answer 23

Vasodilation: Beta 2 *memory: Time 2 Book it
Vasoconstriction: Alpha 1 *memory: Tighten an alpha string for vasoconstriction and sphincter constriction

Question 24

What do dopamine D1 receptors do?

Answer 24

Relax renal vascular smooth muscle

Question 25

What do dopamine D2 receptors do?

Answer 25

Modulate dopamine NT release, especially in the brain

Question 26

What do histamine H1 receptors do?

Answer 26

1. Increase nasal and bronchial mucus production 2. Increase vascular permeability 3. Contract bronchioles 4. Pruritus 5. Pain *memory: Basically everything allergic. Thats why we block them to treat respiratory allergies (ex: diphenhydramine)

Question 27

Why are second generation antihistamines less sedation than first generation?

Answer 27

Don't enter the CNS as well, so don't interfere with histamine NT release

Question 28

What do histamine H2 receptors do?

Answer 28

Increase gastric acid secretion That's why we use them for peptic ulcer, gastritis, and GERD (ex: cimetidine)

Question 29

What do vasopressin V1 receptors do?

Answer 29

Increase vascular smooth muscle contraction *Thats why pitressin, a vasopressin analog that acts on V1 and V2, is used for ICU patients hypotensive crisis

Question 30

What do vasopressin V2 receptors do?

Answer 30

Act on collecting tubules of the kidney to increase water permeability so water can be absorbed (they are ADH receptors... vasopressin = ADH) *Thats why desmopressin is used for central diabetes insipidus

Question 31

Desmopressin acts on V2 receptors so it is used to treat central diabetes insipidus (its basically exogenous ADH). What other completely unrelated disease does it treat, and why?

Answer 31

Von Willebrand's disease because it also increases Factor 8 and vWF release from endothelial cells

Question 32

What GPCR class are alpha 1, alpha 2, beta 1, and beta 2 receptors?

Answer 32

``` *memory: QISS (kiss) the sympathetic nervous system Alpha 1 = Gq Alpha 2 = Gi Beta 1 = Gs Beta 2 = Gs ```

Question 33

What does the M1 parasympathetic postganglionic receptor do?

Answer 33

CNS and enteric nervous system stimulation

Question 34

What does the M2 parasympathetic postganglionic receptor do?

Answer 34

1. Decrease HR | 2. Decrease contractility of ATRIA

Question 35

What does the M3 parasympathetic postganglionic receptor do?

Answer 35

1. Increase exocrine gland secretion (lacrimal, salivary, gastric) 2. Increase gut peristalsis 3. Increase bladder contraction 4. Bronchoconstriction 5. Miosis 6. Ciliary muscle contraction (accomodaiton -- short range focus)