11 - Glucocorticoids Flashcards
Are adrenocorticoids the same as androgens?
NO
What causes the body to induce production of adrenocorticoids?
- Stress
- Stress causes release of corticotropin releasing hormone (CRH) from hypothalamus, stimulating release of adrenocorticotropic hormone (ACTH) from pituitary gland, which stimulates uptake of LDL into adrenal cortical cells to produce adrenocorticoids
What are the most important adrenocorticoids?
Cortisol (hydrocortisone) and aldosterone
What are the functions of glucocorticoids?
- Stimulate gluconeogenesis (liver)
- Stimulate bone loss
- Suppress production of inflammatory mediators, “turning down” immune activity
What is the main mechanism of action for anti-inflammatory effects of glucocorticoids?
- GCs stimulate production of lipocortin (cytosolic protein) that is believed to bind to membrane phospholipids, preventing phospholipase A2 (PLA2) from hydrolyzing ester linkage btwn phospholipid and arachidonic
- Arachidonic acid can’t be released => less production of prostaglandins, leukotrienes, and platelet activating factor inflammatory mediators
What is the outcome of glucocorticoids anti-inflammatory effects?
Inhibition of macrophages in tissues, neutrophils in or near blood, and eosinophils in bronchi
___ is responsible for the majority of glucocorticoid effects
Hydrocortisone
What is the difference btwn hydrocortisone and cortisone? How are they interconverted?
- Hydrocortisone has OH at C-11; cortisone has =O
- Dehydrogenase converts hydrocortisone to cortisone; reductase converts cortisone to hydrocortisone
Why is hydrocortisone not stored in LDL and HDL particles?
B/c it is a stress hormone, so we only want it around when it is immediately needed
What are some adverse effects of glucocorticoids?
- Infections
- Osteoporosis
- Increased CV risk
- Myopathy
- Weight gain/obesity
- Gastric ulcer
- Skin thinning
- Glaucoma, cataract
What is the primary use of glucocorticoids as drugs?
Suppression of inflammation
What are the routes of administration for glucocorticoids as drugs? What is most common?
Oral, IV, IM, inhaled, and topical (most common is topical)
What preparations is hydrocortisone used in?
Ointments and creams (but not o/w lotions) to enhance dermal uptake
Are synthetic glucocorticoids more or less potent than natural glucocorticoids?
More potent
Does hydrocortisone produce any active metabolites?
No