adrenal glands Flashcards
where are the adrenal glands in relation to the peritoneum
retroperitoneal
what embryological tissue are the adrenal cortices derived from
intermediate cortex
what embryological tissue are the adrenal medulla derived from
neural crest cells
what cells are found in the adrenal medulla
chromaffin
modified sympathetic ganglion cells
what are the layers of the cortex
zona glomerulosa
zona fasciculate
zona reticularis
what hormone does the glomerulosa produce
mineralocorticoids (aldosterone
what does the faciculata produce
glucocorticoids e.g. cortisol
what does the reticularis produces
glucocorticoids and androgens
what does the medulla produce
epinephrine
what system controls aldosterone
the renin angiotensin aldosterone system
what is the function of aldosterone
promotes Na+ and water retention, and lower plasma K+
what is the function of glucocorticoids
carbohydrate, lipid and protein metabolism
what hormone controls glucocorticoid secretion
Adrenocorticotropic hormone (ACTH) Produced by that anterior pituitary gland
what is the blood supply to the adrenal cortex
superior, middle and inferior adrenal arteries
short cortical arteries
what is the blood supply to the medulla
blood draining from the cortex containing adreno corticosteroids which influences the production of adrenaline by the medulla
fresh blood in long cortical arteries
what is the long term stress response
retention of sodium and water increased volume and blood pressure proteins and fats converted to glucose increased blood glucose suppression of the immune system
what are the actions of cortison
ability to deal with stress, trauma, infection etc
anti inflammatory
anti allergic
anti immune actions
what are the possible causes of cushings
ACTH releasing pituitary tumour
ectopic ACTH releasing tumour
tumour of the adrenal cortex
administration of therapeutic glucocorticoid drugs
what are the features of cushings
hyperglycaemia muscle wasting due to loss of protein synthesis increase in FFA (free fatty acid) increased insulin release redistribution of fat stores to face, neck, upper trunk buffalo hump tissue oedema hypokalaemia hypertension water and sodium retention GI tract ulceration decrease in protein synthesis
what pathways stimulate aldosterone secretion
increased potassium
ACTH
RAAS
what are the causes of Addison’s disease
Tuberculosis
metastatic tumour
HIV
atrophy due to prolonged steroid therapy
what are the features of Addison’s disease
loss of weight/ appetite, muscle weakness, nausea, vomiting
low plasma glucose
hyponatreamia and hyperkalaemia
dehydration and hypotension
lethargy and dizziness
skin pigmentation
what is the treatment of addison’s
glucocorticoid replacement therapy
intravenous saline if severely dehydrated
what do chromaffin cells produce
catecholamines
controlled by preganglionic sympathetic neurons
