lecture 2- ANS

Question 1

function of a neuron

Answer 1

• neurons conduct AP, carrying information across synapses
• drugs can interupt both axonal conduction and synaptic transmission, ultimately influencing receptos activity

Question 2

receptor selectivity

Answer 2

allows us to selectively inhibit/activate certain biochemical processes

Question 3

nervous system divisions

Answer 3

a) CNS (brain + spinal cord) & PNS (everything else)
b) PNS > ANS (automatic) & S(omatic)NS (voluntary)
c) ANS > SNS (fight or flight) & PSNS (rest and digest)

Question 4

regulation of physiological processes

Answer 4

most structures have both SNS and PSNS innervation, except blood vessels (SNS)

Question 5

which structure only has SNS innervation?

Answer 5

blood vessels

Question 6

how are blood vessels regulated?

Answer 6

• baroreceptor reflex (negative feedback loop)
• autonomic tone is the baseline activation of ANS (balance between SNS and PSNS)

Question 7

anatomy of PSNS

Answer 7

two neurons connected by ganglion

Question 8

anatomy of SNS

Answer 8

two neurons connected by ganglion OR neuron connected to adrenal medulla

Question 9

anatomy of somatic NS

Answer 9

neuron connected to organ/muscle

Question 10

NT of the PNS

Answer 10

acetylcholine, NE, epinephrine

Question 11

acetylcholine released by…

Answer 11

• pre and postganglionic neurons of PSNS
• preganglionic neurons of SNS
• postganglionic neurons of SNS that go to sweat glands

Question 12

NE released by…

Answer 12

postganglionc neurons of SNS (except sweat glands)

Question 13

epinephrine released by…

Answer 13

adrenal medulla

Question 14

receptors of the PNS

Answer 14

a) cholinergic: nicotinic M, nicotinic N, muscarinic 1-5
b) adrenergic: alpha 1, alpha 2, beta 1, beta 2, dopamine (CNS only)

Question 15

nicotinic N

neuronal

Answer 15

a) location
- cell bodies of postganglionic neurons in SNS and PSNS
- cells of adrenal medulla
b) function
- promotes ganglionic transmission in all ganglia of SNS and PSNS
- promotes epi release from adrenal medulla

Question 16

nicotinic M

muscle

Answer 16

a) location
- muscle
b) function
- contraction of skeletal muscle

Question 17

muscarinic

Answer 17

a) location
- all organs regulated by PSNS and sweat glands
b) function
- elicits a response from the organ involved (ie. glandular secretion, SM/bronchi contraction, dec HR, pupil contraction, urination)

Question 18

alpha 1

Answer 18

a) location
- eyes, BV, male sex organs, prostate capsule, bladder
b) function
- pupil dilation, vasoconstriction, ejaculation, bladder contraction

Question 19

alpha 2

Answer 19

a) location
- nerve terminals (presynaptic)
b) function
- regulates NT release

Question 20

beta 1

Answer 20

a) location
- heart and kidney
b) function
- inc HR/force of contraction/speed of impulse
- renin release(helps with vasoconstriction and inc bp)

Question 21

beta 2

Answer 21

a) location
- lung, uterus, arterioles of heart/lung/skeletal muscle/liver
b) function
- bronchodilation, relaxation of uterine SM, vasodilation, skeletal muscle contraction, glycogenolysis

Question 22

dopamine

Answer 22

a) location
- kidney
b) function
- dilates renal blood vessels to increase perfusion

Question 23

adrenergic receptor specificity- NE

Answer 23

a1, a2, b1

Question 24

adrenergic receptor specificity- epi

Answer 24

a1, a2, b1, b2

Question 25

adrenergic receptor specificity- dopamine

Answer 25

a1, b1, dopamine

Question 26

antagonist

Answer 26

a drug that binds to a receptor and prevents the reaction that would occur if the usual NT binds

Question 26

agonist

Answer 26

a drug that binds to a receptor and causes the same reaction as the NT that usually binds

Question 27

muscarinic agonists

Answer 27

- interact with muscarinic receptors (found on organs with PSNS innervation) - leads to inc secretions, gut motility, dec HR/bp | ie. bethanechol

Question 28

bethanechol MOA

Answer 28

binds reversibly to muscarinic cholinergic receptors and activates them

Question 29

bethanechol pharmacological effect

Answer 29

dec HR, inc secretions, bronchoconstriction, GI motility, urination, pupil constriction, muscle aroound vessels dilates

Question 30

bethanechol PK

Answer 30

taken PO (30-60 min onset), 1h duration, minimal systemic absorption

Question 31

bethanechol uses

Answer 31

a) urinary retention: inc voiding pressure - contraindicated in patients with bladder obstruction b) gastroesophageal reflux: increasws gastric motility/emptying - contraindicated in patients with high gastric acid levels or peptic ulcer disease c) counteract anticholinergic side effects

Question 32

bethanechol adverse effects

Answer 32

- CV: bradycardia, hypotension - GI: cramping, diarrhea, inc salivation - lungs: bronchoconstriction (asthma) - thyroid: hyperthyroidism (inc HR, arrythmia)

Question 33

muscarinic antagonists

Answer 33

- prevent activation of muscarinic receptors (block Ach) - inc HR/bp/resp rate, dec GI motility | ie. anticholinergics (atropine)

Question 34

atropine pharmacological effects

Answer 34

inc HR, dec secretions, pupil dilation, mild excitation (small doses), dec GI motility

Question 35

atropine PK

Answer 35

topical (eye), IM, IV, SC

Question 36

atropine uses

Answer 36

a) pre-anasthesia: preventative measures (ie. anticipated drop in HR) b) eyes: pupil dilation for eye exams c) heart: treatment for bradycardia d) GI hypermotility: slows down GI e) biliary colic: relaxes SM when passing gallstone f) antidote for muscarinic agonist poisoning

Question 37

atropine adverse effects

Answer 37

a) eyes: blurred vision/photophobia (prevents constriction/near-focusing), increase intraocular pressure b) secretions: dry mouth (dec secretions), anhidrosis (no sweating) c) bladder: urinary retention d) GI: constipation (dec motility) e) lungs: asthma

Question 38

atropine drug interactions

Answer 38

other drugs that are not muscarinic antagonists (ie. antihistamines, tricyclic antidepressants), will increase muscarinic effect of atropine

Question 39

scopolamine

Answer 39

- muscarinic antagonist, similar to atropine except increased CNS sedation and suppresses nausea - used for motion sickness and palliative care

Question 40

ipratopium bromide

Answer 40

- muscarinic antagonist - given via inhalation fro asthma and COPD, nasal inhalation for rhinitis - minimal systemic absorption so few side effects

Question 41

overactive bladder

Answer 41

- muscarinic antagonists can block M3 receptors on bladder detrusor, reducing urge to void - oxybutinin is an M3 antagonist and side effects include tachy, dry mouth, blurry vision - given as long-acting oral or transdermal route