CH. 5 Noradrenaline

Question 1

what are the two ways NE cells are organized

Answer 1

central
peripheral

Question 2

central NE anatomy

Answer 2

cell bodies in locus coeruleus in the pons (A6)
axons extend to basically the whole forebrain, cerebellum and spinal cord

Question 3

peripheral NE anatomy

Answer 3

sympathetic NS uses NE released from
sympathetic noradrenergic neurons
adrenal gland release

Question 4

true or false; NE transmission in the brain and the body can influence each other

Answer 4

false; NE does not cross the BBB

Question 5

why doesn’t NE cross the BBB

Answer 5

because it is polar and soluble non-polar atoms cross it better

Question 6

what are the two main NEergic receptors?

Answer 6

alpha (a)
beta (b)

Question 7

what are the different types of alpha NE receptors

Answer 7

a1
a2

Question 8

what kind of receptors are all NE recpetors?

Answer 8

metabotropic

Question 9

what 2nd messenger system do a1 receptors work on?

Answer 9

activates phosphoinositide

Question 10

a1 agonist

Answer 10

phenylephrine

Question 11

a1 antagonist

Answer 11

prazosin

Question 12

what 2nd messenger system do a2 receptors work on? where?

Answer 12

inhibit cAMP synthesis
presynapse autoreceptors and postsynaptic

Question 13

a2 agonist

Answer 13

clonidine

Question 14

a2 antagonist

Answer 14

yohimbine

Question 15

what 2nd messenger system do b1/b2 receptors work on?

Answer 15

stimulate adenylyl cyclase to enhance synthesis of cAMP

Question 16

what role does the b1 receptor play in the periphery?

Answer 16

primary receptor found on the heart that increases heart rate when activated

Question 17

b1/b2 agonist

Answer 17

isoprotenerol

Question 18

b1/b2 antagonist

Answer 18

propanolol

Question 19

what behaviours does NE regulate?

Answer 19

sleep/wake cycle
stress and cognition
emotional memory modulation

Question 20

how does NE regulate the sleep wake cycle?

Answer 20

maintains arousal

Question 21

how does locus coeruleus activity vary throughout the sleep-wake cycle?

Answer 21

very silent during REM
little activity during deep sleep
most activity during wakefulness

Question 22

what NE projections are promoting wakefulness?

Answer 22

medial septal
medial preoptic

Question 23

what effects do a1/b receptor agonists have on wakefullness

Answer 23

increases awake times

Question 24

what effect do a2 agonists/ a1 antagonists have?

Answer 24

sedation

Question 25

how does NE regulate stress?

Answer 25

increased NE causes increase in stress/like feelings of anxiety

Question 26

how was the NE/stress relationship tested in humans

Answer 26

virtual version of the elevated plus maze self-reported feelings of anxiety in open or closed arms

Question 26

how does NE regulate cognition?

Answer 26

NE facilitates attention and working memory by activating postsynaptic a2 receptors

Question 27

describe the study used to show NE's effect on working memory

Answer 27

aged monkeys that received an a2 agonist did better on working memory task with a distactor than control

Question 28

true or false; facilitation of PFC functin by NE seems to be because of postsynapse a2 activation rather than just NE release

Answer 28

true

Question 29

what effect does stress have on cognition through NE regulation? why?

Answer 29

excessive increase in NE release by stress impairs PFC function takes PFC 'offline' to prioritize sensory-motor control on behaviour

Question 30

which receptor drives PFC impairments caused by stress?

Answer 30

a1

Question 31

how is NE effect on the PFC regulated between stress and facilitation?

Answer 31

NE has lower affinity to a1 receptors than a2 therefore low amounts of NE facilitate, high amounts shut down

Question 32

how does NE modulate memory consolidation? why?

Answer 32

enhances memory consolidation when in more emotional states emotionally relevant events are more likely to be important to remember

Question 33

how do b1/2 antagonists affect memory?

Answer 33

disrupts enhancement of memory for emotional content no effect on neutral content

Question 34

what study was performed to see how beta-blockers affect memory consolidation?

Answer 34

control was told a neutral story, experimental an emotional story memory recall tested a few days later beta blocker lowered recall of experimental to same as control

Question 35

where in the brain is NE increase seen for emotional memories?

Answer 35

amygdala (main) spatial and instrumental memory (side note)

Question 36

what psychiatric disorder may the NE-memory relationship underlie?

Answer 36

PTSD