Corticosteroids Flashcards
(26 cards)
2 types of corticosteroids and where are they produced?
Glucocorticoids
Mineralocorticoids
Adrenal cortex
Were are GC receptors located
everywhere
Where are MC receptors located
Epithelial cells in kidney. colon and bladder
What are GC used as
anti-inflammatory drugs
What are MC used for and what is an MC example
regulate elctrolyte balance in the kidney
ALdosterone
Why is there low activity of GC in the liver
Low activity in the kidney due to activation of 11- beta- hydroxysteroid dehydrogenase
What do GC do
Bind to GC receptor in cytoplasm
Raise blood glucose level
What do MC do
bind to MC receptor expressed by mainly kidney, epithelial cells of colon and bladder, maintain electrolyte balance
What are the three domains of GC receptors
Activation domain
RNA binding domain
Ligand binding domain
How do steroids receptors act
Bind to DNA as dimers to regulate transcription
GC receptor dimer bind to specific hormone response elements on target genes
Actions of GC
Metabolic
anti-inflammatory
Immunosuppressive
What disease is caused by a decrease in Corticosteroids
Addison’s disease
What disease is caused by an increase in Corticosteroids
Cushing’s syndrome
action of GC on the liver
Decrease in glucose uptake and utilisation
increase in gluconeogenesis
What can hyperglycaemia lead to
Decrease in protein synthesis
Increase in protein breakdown
Can lead to muscle wasting
What are some of the clinical uses of GC
Replacement therapy for addisons disease GC and MC
Anti- inflammatory/immunosuppressive therapy
Autoimmune disease- rheumatoid arthritis
How are GC used in cancer
Increase in cytotoxic drugs
Decrease in cerebral oedema in brain tumour
Weight gain - stimulate appetite
Anti- emetic therapy in conjunction with chemo
Features of Addison’s disease
No steroids are produced from the adrenal cortex
skin pigmentation
discolouring of gums
how are corticosteroids used to treat MSK disease
Treatment with supraphysiologic doses of steroids reduced inflammation
Steroids suppress all phases of early inflammation
Decrease in number of activated macrophages, T- cells,
Decrease in IL-1 , IL -2 production
Decrease in transcription of COX-2 , PLA-2 . IL ZR inhibits AP-1
AE of inhaled steroids
Oral candisis
Increase in pneumonia risk
Increase in blood gluocose
AE of steroids
cushings syndrome symptoms
higher doses can cause negative feedback and supress the efffect
Leucocytosis
How can GC lead to osteoporosis
GC regualte ca 2+/ PO4 2- metabolism
GC regulate collagen synthesis by osteoblasts GCs inhibit Vit D3 induction of genes in osteoclasts
What can cause cushings disease
Tumour in the pituitary
Treatment for cortisol levels
Control cortisol levels
Metyrapone inhibits 11 B - hydox.
