topic 7 - stress and mood disorders

Question 1

conditions for a stressful response

Answer 1

being attacked
- hunger
- cold
- attacking somebody
- overheating

Question 2

what nervous system is involved with stress response

Answer 2

sympathetic nervous system
para-sympathetic nervous system is being inhibited

Question 3

what does the stress response do to the sympathetic nervous system

Answer 3

• constricts blood vessels
• stimulates release of glucose from the liver
• inhibits digestive system in order to get the energy into your bloodstream faster
• inhibits tears and salvation
• relaxes airways so more air can come in
• speeds heartbeat

Question 4

what neurotransmitter used by the post-ganglionic neurons in the sympathetic nervous system

Answer 4

noradrenaline - makes ur heart beat go faster

Question 5

adrenal cortex

Answer 5

cortex is the outer layer of the adrenal gland but think of them as seperate glands
- PVN releases CRF
- releases cortisol which is a glucocorticoid
- one of the main functions of cortisol is to release glucose from stores to keep concentration high in the bloodstream
- it is triggered by the arrival of ACTH from the binding to the receptors
- ACTH triggers the enzymes to start making cortisol and releases it into the bloodstream

Question 6

adrenal medulla as part of the stress response

Answer 6

gets innovation from the pre-ganglionic neurons as part of the sympathetic nevous system which releases acetylcholine onto the adrenal medulla which then releases noradrenaline and adrenaline into the bloodstream
^ triggered by neural signals coming across the pre ganglionic neurons

Question 7

ACTH

Answer 7

released into the bloodstream by the anterior pituitary gland
- CRF triggers the release of ATCH
- CRF is released by neurons in the hypothalamus (para ventricular nucleus, PVN) and their axons release CRF into the bloodstream

Question 8

what hormone will peak first when a stress response is active

Answer 8

adrenaline

Question 9

the two pathways to the two different endocrine logical responses to stress

Answer 9

• sympathetico adrenal medullary axis
• HPA axis - hypothalamo pituitary adrenal axis

Question 10

activation of the stress response

Answer 10

amygdala:
- central nucleus of the amygdala: involved in homeostatic challenges (physical)
- medial nucleus of the amygdala: in response to psychogenic challenges (emotional, feeling uneasy)
- subgenual anterior cingulate cortex (indirect activation, involved with depression as well)

Question 11

direct feedback of cortisol on the PVN

Answer 11

• cortisol binds to glucocorticoid receptors
• this triggers the release of endocannibinoids
• these inhibit the release of glutamate from pre-synaptic terminals onto PVN which also means CRF isn’t being stimulated so not being released
• negative feedback

Question 12

genetic predisposition example

Answer 12

BDNF polymorphism:
- if u have specific type of BDNF you’re more likely:
increased chances of depression
increased sensitivity to stressful life events
increased sensitivity to childhood adversity