ADRENAL DISORDERS Flashcards
Which 3 kinds of steroid hormones does the adrenal cortex produce, with examples?
- Sex steroids (e.g. androgens)
- Mineralocorticoids (e.g. aldosterone)
- Glucocorticoids (e.g. cortisol)
Name 2 functions of mineralocorticoids
- Mineral homeostasis (Increase Na+ and decrease K+)
- Maintain blood volume
What is the main function of glucocorticoids such as cortisol?
Helps body during exposure to stress
Name 3 catabolic effects of glucocorticoids such as cortisol
- Inhibits protein synthesis
- Lipolysis
- Promotes bone resorption
Name 3 anabolic effects of glucocorticoids (e.g. cortisol)
- Stimulates gluconeogenesis (conversion of proteins and fats into glucose)
- Promotes liver glycogen synthesis and storage
- Increases central fat deposition
Why are glucocorticoids used therapeutically as anti-inflammatory and immunosuppressive drugs?
- Decreases vascular permeability
- Decreases WBCs and WBC activity
- Inhibits cell mediated immunity
What are 3 adverse effects of glucocorticoids?
- Increases risk of infection
- Decreased wound healing
- Sodium + water retention
What type of hormones does the adrenal medulla secrete?
Catecholamines (e.g. epinephrine and norepinephrine)
Name 5 steps of adrenal gland regulation
- Stimulus (e.g. stress)
- Hypothalamus secretes CRH (corticotropin releasing hormone)
- CRH stimulates anterior pituitary to release ACTH (adrenocorticotropic hormone)
- ACTH stimulates adrenal cortex to secrete cortisol
- Cortisol inhibits hypothalamus and anterior pituitary
What are 2 terms for a condition of excess cortisol?
Hypercortisolism or Cushing syndrome
What is the most common cause of Cushing syndrome?
Adverse effect of therapeutic glucocorticoids
What is the cause behind primary hypercortisolism?
Adrenal hyperplasia or adrenal tumours that hypersecrete ACTH
What is the cause behind secondary hypercortisolism, also called Cushing disease?
Pituitary adenoma that hypersecretes ACTH
Besides adrenal hyperplasia, adrenal tumours, and a pituitary adenoma, what is another possible cause for excess ACTH leading to hypercortisolism?
Ectopic production of ACTH, e.g. small cell lung cancer
Why do symptoms of hypercortisolism include muscle weakness and osteoporosis?
Cortisol inhibits protein synthesis causing muscle atrophy
Cortisol promotes bone resorption