autonomic NS

Question 1

main integrator of homeostasis

Answer 1

brain- hypothalamus and brain stem

Question 2

2 neuron system in SNS

Answer 2

pregang - ganglia (Ach, nicotinic)

postgang-target (epi or NE, adrenergic)

Question 3

exception to 2 neuron system of SNS

Answer 3

adrenal medulla- pregang synapse directly on chromaffin cells that release epi directly into blood

Question 4

2 neuron system in PNS

Answer 4

pregang to ganglia (ach, nicotinic)

post gang to target (ash, muscarinic)

Question 5

acetyl choline is made from:

Answer 5

acetyl coa and choline

Question 6

acetylcholine is degraded in the synapse by

Answer 6

acetylcholinesterase

Question 7

describe nicotinic ach receptor

Answer 7

ligand gated ion channel that permits Na influx and K efflux

Question 8

in general, muscarinic receptors are…

Answer 8

g coupled

Question 9

type of muscarinic receptor at SA node

Answer 9

M2

Question 10

MOA of M2 receptors at SA node

Answer 10

decrease HR by: 1) binding K-K(ach) channels and hyperpolarizing and also 2) inhibit t-type Ca channels

Question 11

type of muscarinic receptor on bronchial smooth mm

Answer 11

trick! both M2 and M3

Question 12

action of M2 on bronchial smooth mm

Answer 12

M2 inhibits GaS to cause contraction

Question 13

action of M3 on bronchial smooth mm

Answer 13

M3 stimulates Gaq to cause contraction

Question 14

steps in epinephrine synthesis (4)

Answer 14

tyrosine –> dopa (tyrosine hydroxylase)
dopa –> dopamine (dopa decarboxylase)
dopamine –> NE (dopamine b-hydroxylase)
NE –> epinephrine (PNMT)

Question 15

m/c NT released from postganglionic sympathetic neurons

Answer 15

norepinephrine

Question 16

how is epinephrine formed in the adrenal medulla?

Answer 16

chromatin cells have PNMT to convert NE –> epi

Question 17

a receptors have a greater affinity for …

b receptors have a greater affinity for …

Answer 17

a - NE

b- epinephrine

Question 18

all of the adrenergic receptors are … except for …

Answer 18

all of the adrenergeic receptors are postsynaptic except for a2 which is presynaptic

Question 19

mechanism typically used by B receptors

Answer 19

GaS

Question 20

mechanism typically used by a receptors

Answer 20

Gaq

Question 21

adrenergic receptors in bronchial smooth mm

Answer 21

B2

Question 22

adrenergic receptors in heart

Answer 22

B1

Question 23

adrenergic receptors on vascular smooth mm

Answer 23

a

Question 24

mechanism by which HR is increased by activation of SNS

Answer 24

SA node has B1 receptors, stimulation of these receptors leads to GaS mechanism and increased activity of PKA, PKA increases currents of funny Na channel and t-type Ca channel = depolarization

Question 25

mechanism of vasoconstriction by SNS

Answer 25

vascular smooth mm has a receptors, activate Gaq = increased Ca = contraction

Question 26

mechanism of bronchial smooth mm relaxation by SNS

Answer 26

bronchial smooth mm has B2 receptors, activate GaS, increases cAMP levels that inhibit MLCK and promote relaxation

Question 27

which arm of the autonomic ns has greater control over resting HR

Answer 27

parasympathetic

Question 28

action of muscarinic receptors on bronchial smooth mm

Answer 28

M3- uses Gaq mechanism to increase Ca and promote contraction

Question 29

2 ways to treat asthma

Answer 29

1- b2 agonist (albuterol) = increase cAMP and inhibit MLCK | 2- anticholinergic (ipratropium)= inhibit Gaq

Question 30

ANS receptors on detrusor mm

Answer 30

SNS- b3- promote relaxation via GaS | PNS- M3- promote contraction via Gaq

Question 31

ANS receptor on urethra

Answer 31

SNS-a- promotes contriction via Gaq

Question 32

treatment of urge incontinence

Answer 32

anticholinergics to inhibit M3

Question 33

treatment of stress incontinence

Answer 33

a agonist to increase urethral constriction

Question 34

treatment of overflow incontinence

Answer 34

a antagonist to relax urethra and allow for complete bladder emptying

Question 35

locations of baroreceptors

Answer 35

carotid, aorta

Question 36

actions of baroreceptors

Answer 36

``` sense stretch (indicting increased BP) sends signal to brain that BP increased brain sends signal to down regulate SNS (decrease HR, decrease vasoconstriction) and to up regulate PNS (further decrease HR) ```