ANS anatomy & physiology 5

Question 1

________________ is the neurotransmitter of most postganglionic sympathetic fibers

Answer 1

Norepinephrine

Question 2

What are the nine types of adrenergic receptors

Answer 2

Alpha 1: a1A, a1B, a1D
Alpha 2: a2A, a2B, a2C
Beta: B1, B2, B3

Question 3

Neurotransmitter release is modulated by activation of ______________________ at cholinergic and adrenergic synapses

Answer 3

prejunctional autoreceptors or heteroreceptors

Question 4

Describe the sympathetic pathway of the adrenal medulla.

Answer 4

Preganglionic neurons release ACh onto chromaffin cell effectors (targets)- no postganglionic neurons

Question 5

Postganglionic sympathetic neurons release _____________ at sweat glands

Answer 5

ACh

Question 6

How many different chemical messengers can be co-released with NE or ACh?

Answer 6

over a dozen

Question 7

The alpha 1 receptor as a whole has the following functional responses:

Answer 7

vasoconstriction
promotes cardiac growth and remodeling

Question 8

The cellular response of activation of the alpha1 receptor is

Answer 8

couple to Gq to activate PLC: increased IP3/DAG, increased Ca2+, PKC
increased Na+/H+ exchanger

Question 9

The cellular response of activation of the alpha 2 receptor is

Answer 9

coupled to Gi to inhibit adenylyl cyclase to decrease cAMP, decrease PKA activity

Question 10

The functional response of alpha 2 activation is

Answer 10

vasoconstriction
decreased neurotransmitter release and release from adrenal medulla

Question 11

The cellular response of activation of the beta receptors is

Answer 11

coupled to Gs to activate adenylyl cyclase= increased cAMP, increased PKA activity
activates L-type Ca2+ channels

Question 12

Beta 1 blockers functional response include

Answer 12

positive chronotropic, dromotropic, & inotropic action on the heart
increased renin release

Question 13

Beta 2 blockers functional response includes

Answer 13

relaxation of bronchial, gastrointestinal and uterine smooth muscle
decreased secretions from bronchial glands
vasodilation

Question 14

Beta 3 blockers functional response includes

Answer 14

lipolysis & thermogenesis

Question 15

One autoreceptor on each nerve terminal mediates _____________ neurotransmitter release, the positive feedback cycle.

Answer 15

increased

Question 16

Two receptors on each nerve terminal, one autoreceptor and one heteroreceptor, mediate __________________ neurotransmitter release

Answer 16

decreased

Question 17

Which receptor is responsible for decreased insulin release?

Answer 17

alpha 2 receptors

Question 18

Which receptor is responsible for decreased preganglionic AcH release?

Answer 18

alpha 2 receptors

Question 19

Which receptor is responsible for decreased preganglionic NE release?

Answer 19

alpha 2 receptors

Question 20

Which receptor is responsible for skeletal muscle vasodilation?

Answer 20

beta 2 receptors

Question 21

Which receptor is responsible for uterus smooth muscle relaxation?

Answer 21

beta 2 receptors

Question 22

Which receptor is responsible for bronchodilation?

Answer 22

beta 2 receptors

Question 23

Which receptor is responsible for increased heart rate?

Answer 23

beta 1 receptors

Question 24

Which receptor is responsible for mydriasis?

Answer 24

alpha 1 receptors

Question 25

Which receptor is responsible for increased renin release?

Answer 25

beta 1 receptors

Question 26

Which receptor is responsible for pyloric sphincter contraction?

Answer 26

alpha 1 receptors

Question 27

Which receptor is responsible for pilomotor muscle contraction?

Answer 27

alpha 1 receptors

Question 28

Which receptor is responsible for increased dromotoropy?

Answer 28

beta 1 receptors

Question 29

What is the rate limiting step in catecholamine synthesis?

Answer 29

tyrosine hydroxylase

Question 30

Postganglionic sympathetic fibers to sweat glands are:

Answer 30

cholinergic

Question 31

Contraction of this intraocular muscle causes mydriasis.
a. ciliary
b. radial
c. circular
d. orbitalis

Answer 31

b. radial

Question 32

Control of pupil diameter in the eye is an example of the

Answer 32

SNS and PNS acting in a synergistic or cooperative manner

Question 33

Contraction of the ____________ muscle of the iris causes mydriasis

Answer 33

dilator pupillae (radial)

Question 34

Contraction of the ____________ muscle causes miosis

Answer 34

sphincter pupillae (circular)

Question 35

The sympathetic division of the heart wields an overall

Answer 35

excitatory effect on the heart

Question 36

The parasympathetic division of the heart produces an overall

Answer 36

inhibitory effect on the heart

Question 37

The salivary glands are an example of ______________ elicited by sympathetic and parasympathetic innervation of the same target tissue

Answer 37

complementary physiologic responses

Question 38

Activation of parasympathetic pathways of the salivary glands leads to

Answer 38

copious watery saliva via ACh acting at M3 receptors

Question 39

Activation of postganglionic sympathetic fibers at the salivary glands leads to

Answer 39

thick, viscous secretion via the actions of NE at a1 & Beta receptors

Question 40

Many organs or tissues receive input from only ________ of the ANS

Answer 40

one division- either sympathetic or parasympathetic

Question 41

Organs or tissues that have parasympathetic innervation only include

Answer 41

lacrimal glands
ciliary muscle (for near vision accommodation)
nasopharyngeal glands

Question 42

Organs or tissue that have sympathetic innervation only include:

Answer 42

adrenal medulla
most blood vessels
gallbladder
kidney
exocrine sweat glands
erector pili (pilomotor) muscles

Question 43

The salivary glands are an example of ______________ physiologic responses elicited by sympathetic and parasympathetic innervation of the same target tissue.

Answer 43

Complementary

Question 44

Which heart tissue shows little response to ACh?

Answer 44

ventricular muscle (myocytes)