chapter 2: autonomic pharmacology

Question 1

increased secretion: think? drying of secretion: think?

Answer 1

increased secretion: muscarinic agonist (both sympathetic cholinergics and parasympathetics). decreased secretion: muscarinic antagonist.

Question 2

B2 receptors are generally not innervated. what does this mean?

Answer 2

NE will hardly work on B2, while the hormone Epi will work on B2! (not only bc not innervated, but also bc of ligand-receptor intxn)

Question 3

block reflex tachycardia (when given an antihypertensive)?

Answer 3

m2 receptor antagonist

Question 4

block reflex bradycardia (when BP goes up)?

Answer 4

B1 receptor antagonist

Question 5

formula for BP and CO

Answer 5

BP = TPR x CO. CO = HR x SV

Question 6

two autonomic processes that must be considered when trying to reduce BP

Answer 6

1. reflex tachycardia 2. reflex renin-angiotensin-aldosterone mediated vasoconstriction & increased blood volume.

Question 7

how can we distinguish if miosis is caused by (1) muscarinic agonism or (2) a1 antagonism? (or, mydriasis is caused by (1) a1 agonism or (2) muscarinic antagonism?

Answer 7

muscarinic = blurry vision!

Question 8

2 ways to get miosis

Answer 8

(1) muscarinic agonism on sphincter muscle (blurred vision) or (2) alpha-1 antagonism on radial muscle (no blurred vision). muscarinic agonism will additionally cause accommodation (contraction of ciliary muscle). distance = blurry.

Question 9

2 ways to get mydriasis

Answer 9

(1) alpha-1 agonism of radial muscle (no blurred vision). (2) muscarinic antagonism of sphincter muscle (blurred vision) muscarcinic antagonism will additionally cause loss of accommodation (no contraction of ciliary muscle –> cycloplegia) close = burry.

Question 10

contraction of ciliary muscle..

Answer 10

thickens lens (focus for near vision)

Question 11

innervation of ciliary muscle

Answer 11

ONLY muscarinic for accommodation

Question 12

medical use of botulinum toxin (5)

Answer 12

local injection. intentional decrease in Ach at N1 (1) blepharospasm (2) dystonia (3) strabismus (4) wrinkles (5) hyperhydrosis (decrease secretions at M3 receptors)

Question 13

3 things to think of w/ muscarinic activity

Answer 13

1. heart 2. secretions 3. smooth muscle contraction

Question 14

muscarinic antagonist / agonist subtype specificity?

Answer 14

there is none! will affect all muscarinics!

Question 15

M2 receptors activation (2)

Answer 15

(1) SA node: decrease HR (chronotropy) (2) AV node: decrease conduction velocity (dromotropy). no effect on ventricles / purkinje system (ionotropy)

Question 16

M3 receptor activation; which (5) organs? effects for each.

Answer 16

(1) eye. sphincter: contraction, miosis. ciliary muscle: contraction, accommodation (2) lungs. bronchioles: contraction, bronchospasm. glands: secretion (3) GI tract: stomach, increased motility. intestine, contraction (diarrhea, involuntary defecation). note also M1. (4) bladder; contraction of detrusor, relaxation of trigone/sphincter –> voiding, urinary incontinence. (5) sphincters; relaxation, except lower esophageal, which contracts. (6) glands; increased secretion (sweat, salvation, lacrimation (7) blood vessels endothelium; dilation (via NO/endothelium-derived relaxing factor) –> no innervation, no effects of indirect agonists)

Question 17

induce miosis for..

Answer 17

glaucoma! (muscarinic agonist)

Question 18

which part of ANS controls ventricular muscle? blood vessel

Answer 18

ONLY sympathetic. parasympathetic only works on AV and SA nodes.

Question 19

M1 receptor activation; which (1) organ and effect

Answer 19

glands in GI tract, secetion. note GI tract also has M3 in stomach (increased motility, cramps) and Intestine (contraction –> diarrhea, involuntary defecation)

Question 20

endothelium (blood vessel) receptors

Answer 20

no innervation, no indrect agonist effect. only under sympathetic control. can affect w/ systemic drugs though. nitric oxide from arginine.