lecture 8 - autonomic NS

Question 1

axons of postganglionic neurons exit the sympathetic trunk ganglion in 4 ways

Answer 1

1. join spinal nerves
2. form cephalic periarterial nerves
3. for sympathetic nerves
4. form splanchnic nerves

Question 2

4 ways postganglionic neuron axons exit the sympathetic trunk ganglion - 1. joint spinal nerves

Answer 2

axon follows grey com rami to rejoin spinal nerve

Question 3

4 ways postganglionic neuron axons exit the sympathetic trunk ganglion - 2. form cephalic periarterial nerves

Answer 3

nerve exits trunk ganglion, wraps around an artery (such as carotid artery) and extends to the head to innervate skin of the face and its glands

Question 4

4 ways postganglionic neuron axons exit the sympathetic trunk ganglion - 3. form sympathetic nerves

Answer 4

exits trunk ganglion and extends to visceral effectors in thoracic cavity

makes up axons that form cardiac plexus

Question 5

4 ways postganglionic neuron axons exit the sympathetic trunk ganglion - 4. form splanchnic nerves

Answer 5

exit trunk ganglia NOT thru grey com rami, and becomes a splanchnic nerve

these innervate blood vessels in abdominopelvic organs, and chromaffin cells in suprarenal medulla

Question 6

parasympathetic preganglionic cell bodies are found in:

Answer 6

4 cranial nerve nuclei (3,4,9,10)
and lateral grey matter of s2-s4

this is called the craniosacral division

Question 7

are parasympathetic ganglia close or far from the CNS

Answer 7

far, this means preganglionic neruons are long, and post ganglionic neurons are short, the opposite of sympathetic

Question 8

how to preganglionic nerves work in the parasympathetic half if some of the nuclei are in cranial nerves?

Answer 8

they emerge as part of the cranial nerve and split off

Question 9

terminal ganglia

Answer 9

where all preganglionic neurons in PSNS synapse with postganglionis neurons

located very close or in the wall of the effector

Question 10

how many postganglionic neurons can one preganglionic neuron synapse with in the terminal ganglia?

Answer 10

4-5, allows for specific localized response

Question 11

cranial parasymapthetic outflow is formed by

Answer 11

axons taht extend from the brainstem in the 4 cranial nerves

Question 12

sacral parasympathetic outflow is formed by;

Answer 12

axons from teh anterior roots of s2-s4 as spinal nerves

Question 13

80% of craniosacral outflow is transmitted by

Answer 13

the vagus nerve

is supplies the heart, airways, adn abdominal area

Question 14

4 ganglia in the cranial outflow

Answer 14

ciliary
pterygopalatine
submandibular
otic

Question 15

pelvic splanchnic nerves branch from

Answer 15

s2-s4

Question 16

preganglionic axons do one of two things in the PSNS

Answer 16

1. join cranial nerves (PS cranial outflow)
2. exit is splanchnic nerves from the sacrum (PS Sacral outflow)

Question 17

cholinergic neurons release

Answer 17

ACh - acetylcholine

Question 18

adrenergic neurons release

Answer 18

NE - norepinephrine

Question 19

what neurons are cholinergic (release ACh)

Answer 19

• all preganglionic neurons
• all parasympathetic postganglionic neurons
• symapthetic postganglionic neurosn that supply sweat glands, and smooth muscle for blood vessels

Question 20

ACh can cause:

Answer 20

excitation or inhibition depending on the type of receptor and cell involved

Question 21

duration of action of ACh (short/long), why?

Answer 21

short, because acetycholinesterase quickly degrades it

Question 22

cholinergic receptors (what is it, waht types are there)

Answer 22

integral membrane proteins in postsynaptic cell membranes

two types: nicotinic and muscarinic

Question 23

nicotinic receptors

Answer 23

type of cholinergic receptor
- ionotropic
- activation causes excitation
- found on postganglionic neurons
- nicotine binds to these

Question 24

muscarinic receptors

Answer 24

type of cholinergic receptor
- metabotropic
- activation causes either excitation or inhibition
- found on all parasympathetic effectors
- muscarine binds to these

Question 25

only thing that can bind to both nicotinic and muscarinic recptors

Answer 25

ACh

Question 26

where are nicotinic receptors found?

Answer 26

postganglionic cells, all types of them

Question 27

where are muscarinic receptors found?

Answer 27

most effectors

(all PS effectors, some sympathetic (sweat/blood/smooth M)

Question 28

most sympathetic postganglionic neurons are

Answer 28

adrenergic

Question 29

duration of action of NE is (long/short), why?

Answer 29

long, enzymes have to inactivate it

Question 30

why are effects triggered by adrenergic neurons typically longer lasting?

Answer 30

because NE takes longer to be inactivated by enzymes

Question 31

alpha 1 and beta 1 receptors generally produce (excitation / inhibition)

Answer 31

excitation

Question 32

a2 and b2 receptors generally produce

Answer 32

inhibition

Question 33

Beta 3 receptors are only found on

Answer 33

brown adipose tissue, controls thermogenesis

Question 34

alpha and beta receptors are subtypes of

Answer 34

adrenergic receptors

Question 35

agonist

Answer 35

substance that binds to and activates a receptor

mimics a NT or hormone

Question 36

antagonist

Answer 36

substance that binds to and blocks a receptor

prevents NT or hormone function

Question 37

example for adrenergic agonists

Answer 37

increased NE release to increase HR

Question 38

example for adrenergic antagonist

Answer 38

decrease NE

Question 39

example for cholinergic agonists

Answer 39

stimulate ACh release to increase muscle contraction

Question 40

example for cholinergic antagonists

Answer 40

decrease release of ACh