Exam 4

Question 1

“fight or flight”

Answer 1

sympathetic nervous system

Question 2

“rest and digest”

Answer 2

parasympathetic nervous system

Question 3

which neurotransmitter is released by the preganglionic fibers of the SNS?

Answer 3

acetylcholine

Question 4

what receptor on the SNS postganglionic fiber receives ACh from the presynaptic fiber?

Answer 4

nicotinic receptor

Question 5

which fibers of the SNS are short?

Answer 5

preganglionic

Question 6

which fibers of the SNS are long?

Answer 6

postganglionic

Question 7

what neurotransmitter is released from the postganglionic fibers of the SNS?

Answer 7

(mostly) norepinephrine

Question 8

what type of receptor on the effector organ receives NE from the postsynapatic fiber in the SNS?

Answer 8

adrenergic receptor (alpha/beta)

Question 9

what neurotransmitters do adrenergic receptors accept?

Answer 9

norepinephrine
epinephrine
dopamine

Question 10

which neurotransmitter causes a negative feedback loop in the SNS?

Answer 10

norepinephrine

Question 11

describe how norepinephrine is synthesized

Answer 11

tyrosine –> DOPA –> dopamine –> norepinephrine

Question 12

what is the rate-limiting step in the synthesis of norepinephrine?

Answer 12

conversion of tyrosine –> DOPA

Question 13

which enzyme catalyzes the transformation of tyrosine to DOPA?

Answer 13

tyrosine hydroxylase

Question 14

what happens to convert dopamine to norepinephrine?

Answer 14

dopamine is beta-hydroxylated

Question 15

what happens to convert norepinephrine to epinephrine?

Answer 15

norepinephrine is methylated in the adrenal medulla

Question 16

what are the three ways norepinephrine is metabolized?

Answer 16

1. reuptake by postganglionic fiber
2. degraded by MAO or COMT
3. dissolves away

Question 17

how much epinephrine vs norepinephrine is released from the adrenal medulla?

Answer 17

80% epinephrine
20% norepinephrine

Question 18

which cranial nerves does the PNS arise from?

Answer 18

CN III
CN VII
CN IX
CN X

Question 19

what type of receptors on the postganglionic fibers receive ACh from the preganglionic fibers in the PNS?

Answer 19

nicotinic receptors

Question 20

in the PNS, what are the receptors on the target/effector organs that receive ACh from the postganglionic fibers?

Answer 20

muscarinic receptors

Question 21

how is acetylcholine metabolized?

Answer 21

cleaved by acetylcholinesterase into acetate ion and choline

Question 22

what does alpha 1 stimulation cause?

Answer 22

vasoconstriction, increased SVR

Question 23

what does beta 1 stimulation cause?

Answer 23

increased inotropy, chronotropy, and conduction

Question 24

what does beta 2 stimulation cause?

Answer 24

smooth muscle relaxation in the vasculature and in the bronchial tree?