Glucocorticoids Flashcards
What does adrenal cortex release (3)?
Cortisol (glucocorticoid), Aldosterone (mineralocorticoid), and Androgens (converted to Testosterone)
What does the Adrenal medulla release?
NE and E (more)
What is the hypothalamic pituitary adrenal axis?
Hypothalamus – CRH —> Anterior Pit — ACTH —> Adrenal Cortex —> Cortisol, Aldosterone, Androgens
Cortisol tells AP and Hypothalamus to do less in negative feedback.
What is the mechanism of glucocorticoids?
Glucocorticoid receptors in cytoplasm bind to GC and complex enters the nucleus to alter transcription.
What do GC do in the body (6) ?
1) Stimulates metabolic (catabolic)
2) Immunsupression
3) Anti-inflammatory
4) Mineralocorticoid activity
5) Adrenal Insufficiency
6) Emotional disturbance
What are the metabolic functions of GC (5) ?
Stimulate :
1) Lipolysis (fat and back)
2) muscle wasting
3) insulin resistance
4) Osteoporosis
5)Increased BP
What are the other actions of glucorticoids (3)?
1) Mineral corticoid activity (fluid retention, increase BP)
2) Adrenal insufficiency (fucks negi feedback loop)
3) Emotional disturbance (insomnia, euphoria followed by depression)
What are gluco-corticoid uses in non-adrenal disorders (5)
1) Allergy (bee sting, PUPP rash (topically in preg)
2) Asthma-pulmonary disease
3) Arthritis-bone joint inflammation
4) GI disease/IBS
5) Suppress organ transplant rejection
What are the causes of Cushing’s syndrome?
Endogenous - tumor in pituitary
Exogenous excessive high potency glucocorticoids use
What are the symptoms of Cushing’s syndrome (7)
1) Buffalo hump, moon face, abdominal fat (↑lipolysis ).
2) Pink/purple stretch marks, poor wound healing, thinning of skin, weak muscle (↑ proteolysis of connective tissue and muscle). Anti inflammatory action can also impair wound healing
3) Hyperglycemia (↑ gluconeogenesis
4) Bone loss (↓bone Ca 2+
5) High blood pressure (↑ epinephrine aldosterone
6) Adrenal insufficiency (negative feed back inhibition of CRF/ACTH release).
Emotional disturbance (likely due to multiple factors).
What does the Hypothalamic - Pituitary - Thyroid Axis do?
Hypothalamus secretes TRH into anterior pituitary –> TR (releasing)H stimulates AP to make TS(stimulating)H —? TSH stimulates growth of the Thyroid gland which releases T4 and T3 —> Tr/T4 cause negative feedback inhibition of TRH and TSH
What is the active Thyroid hormone and which is the more predominant Thyroid hormone?
T4 - more prevalent (metabolized to T3)
T3 - active hormone
What are the general effects of T3 and T4 (3)?
Sympathetic (increased SNS nerve activity, increased O2 consumption)
Metabolic (lipolysis, glycogenolysis, proteolysis, increased O2 consumption)
Grow and development (bone, nervous system)
What are the effects of T3/T4 on special populations?
In children - bone growth, fetus - brain growth, in women - hormonal cycle
What are the symptoms of hypothyroidism?
Hypothyroidism is associated with decreases in sympathetic nerve activity, metabolism and growth, e.g., fatigue, cold intolerance, slow metabolism, weight gain, decreased HR and slowed mental activity, impaired fertility, increased risk miscarriage and preterm birth, pre-eclampsia, gestational hypertension
Even subclinical hypothyroidism should be treated.
