HPA Axis Flashcards
___ (duration) stress is more harmful to health than ___ stress due to its sustained impact
chronic; acute
What two hormones does the PVN of the hypothalamus release and where do they act on?
Vasopressin, CRH; anterior pituitary
The anterior pituitary releases ___ into the blood where it causes the ____ ___ to release _____
ACTH; adrenal cortex; cortisol
The SNS releases ___ during stress which activate the ___ ___
catecholamines; HPA axis
Both the HPA axis and the SNS work to downregulate the ___ system during stress and increase these 3 energy providing processes
immune; gluconeogenesis, glycogenolysis, lipolysis
____ is the most effective range of the U HPA axis curve
eustasis
Good stress can increase the capacity of the HPA axis which is known as
hyperstasis
Glucocorticoids like cortisol are responsible for ___ ___ for both CRH and ACTH
feedback inhibition
The __ receptor works at ____ levels of cortisol while the __ receptor, due to their lower affinity, is responsible for regulation of the ____ ____
MR; GR; stress response
The immune system, ____ in particular, upregulate the HPA axis
cytokines
____, ___ stressors predispose the HPA axis to dysregulation
unpredictable, chronic
Cortisol levels are highest around _ am, then decrease all day to their valley _ hour(s) before you go to sleep
9; 1
__ cortisol measurements are the best for short term, __ measurements can be used for 24 hour levels, and long term can be measured in the ___
Saliva; urine; hair
The dexamethasone test _____ HPA axis activity, so cortisol levels should __ after injection
suppresses; decrease
Peripheral levels of ___ are also used to check HPA axis activity
GR
MDD reduces ___ ___ by cortisol, resulting in HPA axis ___
feedback inhibition; hyperactivity
MDD patients have ____ size of their hypothalamus and pituitary, don’t show cortisol ____ after dexamethasone injection, and have ____ GR receptor levels
increased; suppression; decreased
Patients with ____ disorder show all of the same HPA axis dysregulations as MDD patients, in both the manic and depressive states
bipolar
Both bipolar and MDD patients have ___ cortisol levels upon awakening
increase
People at risk for depression have HPA axis ____ but ___ faster than full blown depressed people
dysregulation; recover
PTSD patients show ___ of HPA axis activity after dexamethasone challenge
hyper suppression
In PTSD, there is a ___ HPA axis activity at baseline but an _____ level of activity in response to a stressor
decreased; increased
People who experience childhood trauma have increased ___ of the GR receptor promotor
methylation
Functional polymorphisms of the _____ gene increase your risk of PTSD
FKBP5
HPA axis elevation occurs only in the ____ phase of schizophrenia, not the ___ phase
acute; chronic
___ ____ ____ is correlated to ___ HPA axis activity, and normalizing the HPA axis may result in less symptoms
First episode psychosis; higher
GR agonists are antidepressive by enhancing _____ ___, while GR antagonists are antidepressive by limiting ___ ___
feedback inhibition; downstream effects
