Adrenal Glands Flashcards
General Role of Adrenals
and location
Located on kidneys,
play major role in response to stress
Adrenal cortex stimulated by ….. releases…….
Adrenal Cortex- 80% of weight-
stimulated by ACTH from pituitary gland
- Zona glomerulosa- aldosterone
- Zona fasciculata- cortisol, cortisone and corticosterone
- Zona reticularis- aldosterone, androgens and estrogens, and glucocorticoids
**we will not be asked which zona produces what?
Adrenal Medulla stimulated by ….. releases…….
Adrenal Medulla- stimulated by sympathetic nervous system
Secretes epinephrine and norepinephrine
- What percentage of epi and norepi are from the chromaffin cells of the Adrenal Medulla?
- What percentage is found nerve terminals?
Why do we care?
- 30% of epi and nor epi are from the adrenal medulla
- 70% of epi and norepi are found in nerve terminals
The epi and norepi coming from the adrenal medulla are sectreted into the blood stream and considered hormones.
The 70% of epi and norepi found in the nerve terminals are considered neurotransmitters.
This is why epi and norepi are each considered both a hormone and neurotransmitter
What is a reason that epi and norepi being considered both a neurotransmitter and hormone is good (according to Dr. T)?
The redundancy allows us to still make these important substances if something stops working (like the adrenal gland)
What are the three categories of hormones secreted by the adrenal cortex?
Glucocorticoids
Mineralcorticoids
Adrenal estrogens and androgens
What is the most important glucocorticoid?
Cortisol
what are three roles of cortisol?
Metabolic
Anit-inflammatory
Growth-Suppressing
Explain the metabolic role of cortisol
What are 4 big effects we may see?
–Metabolic- stimulates protein catabolism (connective tissue breakdown) and glucose formation (increases fat deposition, especially abdomen, cheeks, supraclavicular)
•May have
- severe muscle wasting,
- diabetes,
- ovarian disease,
- obesity
Explain the anti-inflammatory role of cortisol
What big effects may we see?
What did dr. t remind us of?
–Anti-inflammatory-
- decrease T cell formation and function,
- suppress cytokines (immune response),
- stabilize lysosomes;
may see poor wound healing
If given as an anti-inflammatory, will shut down everything down below it in the inflammatory cycle/cascade (such as when comparing it to NSAIDS)
Explain the growth-suppressing role of cortisol
What big effect may we see?
–Growth-suppressing-
- inhibition of bone formation,
- lead to osteoporosis
May see pathological fractures
What is the main Mineralocorticoid relased by the adrenal cortex?
aldosterone
What are two main functions of Aldosterone?
conserves sodium
inhibits reabsoprtion of potassium (rids body of potassium)
Aldosterone: What is the purpose of conserving sodium and eliminating potassium?
–Conserves sodium, thereby increasing blood volume
- •Renin-angiotensin-aldosterone system (RAAS, or RAS) – regulates blood pressure and fluid balance, stimulated by low blood pressure
–Inhibits renal reabsorption of potassium
Aldosterone: how is this hormone related to pharma blood pressure control
•Potassium sparing drugs can be used to control BP
Wikipedia says they also promote excretion of sodium
Drugs that interfere with the secretion or action of aldosterone are in use as antihypertensives, like lisinopril, which lowers blood pressure by blocking the angiotensin-converting enzyme (ACE), leading to lower aldosterone secretion. The net effect of these drugs is to reduce sodium and water retention but increase retention of potassium. (wikipedia)
How do the hormones of the adrenal cortex related to anabolic steroids use?
People who take anabolic steroids, will get into problems with endocrine dysfunction (roid rage, connective tissue problems, out of control muscle hypertrophy, nausea and vomiting).
Because the Adrenal Cortex secretes adrenal estrogens and androgens (so anabolic steroids mess with this process)
What is cortisol released based on?
When is cortisol the highest and how does this affect other hormones?
Circadian release.
Best cortisol levels between 6 am and 6pm.
- There will be times when people have more energy (morning)
- Everything cortisol influences will be timed based on when cortisol is high.
T/F: both too much or too little cortisol will interfere with tissue repair and healing
True
Cortisol is important, but it must be balanced. If there is too much or too little, it will interrupt repair.
How does cortisol block early stages of inflammation? (5)
•Block early stages of inflammation before it begins
- –Stabilize lysosomal membranes
- –Decrease capillary permeability
- –Decrease migration of WBC’s into area and decrease phagocytosis
- –Immune suppression decreased lymphocyte reproduction
- –Attenuates fever by decreasing release of interleukin-1
How does cortisol produce rapid resolution after inflammation has begun to promote healing? (4 ish)
Rapid resolution after inflammation has begun to promote healing, less well understood how
- –By blocking factors promoting inflammation as in early stages of inflammation
- –Possibly
- •Mobilizing amino acids for repair
- •Increasing glucogenesis- energy for repair
- •Increased fatty acids- again energy for repair
- •Inactivation or removal of inflammatory factors
(not really sure I understand this slide)
What can be done to treat deficienecy in mineralcorticoids?
Is it successful?
Drawbacks? (4)
use mineralocorticoid agonist drugs
•Replacement therapy- usually successful
–Can cause hypertension due to increase in sodium and water retention (but this is treatable too)
–Peripheral edema, weight gain and hypokalemia can be side effects
How do mineralocorticoide antagonist drugs work?
What are they for?
What precautions?
•Bind to aldosterone receptor blocking it
–Diuretics resulting in sodium and water excretion
–Must be careful to treat hypertension by excreting sodium and water while sparing potassium (more on that when we talk about the kidney)
What usually causes primary adrenal insufficiency?
what is another name for it?
- Primary adrenal insufficiency – usually is from destruction of gland through autoimmune disease
- Also called Addison’s Disease
how do you treat addison’s dz?
•Hyposecretion can be treated by administering cortisol
