the adrenal gland Flashcards
what are the two adrenal glands
adrenal medulla and cortex
what is secreted by the adrenal cortex
steroid hormones like sex hormones, glucocorticoids and mineral corticoids
what is the secretion of glucocorticoids controlled by
adrenocorticotropic hormone
what is the secretion of mineralocorticoid hormone controlled by
renin angiotensin aldosterone system to release aldosterone to act in the nephrons
what is a disorder of the adrenal cortex
adrenal corticol carcinomas, malignant tumours
which section of the adrenal gland produces cortisol
the adrenal cortex
which part of the adrenal gland is the cortex
the outer part
which part of the adrenal gland is the medulla
the inner part
what does the adrenal medullar produce
adrenaline and noradrenaline
what is the secretion of adrenaline and noradrenaline controlled by
the sympathetic nervous system
what do the adrenaline and noradrenaline hormones fall into the category of
catecholamine hormones
what is addisons disease
destruction of both adrenal glands leading to failure of secretion of all the adrenal corticol hormones
what are the systemic effects of addisons disease
weakeness
tiredness
skin pigmentation
postural hypotension
hypovolaemia (low blood volume)
low blood sodium
what causes addisons disease
destruction of both adrenal glands
when does the adrenal medulla reinforce the actions of the sympathetic nervous system
under the conditions of stress
what is the name for adrenal medulla tumours
phaeochromaocytoma
what are pheochromocytoma
benign tumours of the chromaffin cells leaeding to too much production of adrenalin and noradrenaline
what are the systemic effects of pheochromocytomas
hyperactivity of the sympathetic nervous system leading to sweating, palpitations, and hypertension
what does the adrenal cortex divide itself into
- zona glomerulosa
- zona fasciculata
- zona reticularis
what is the zona glomerulosa
most superficial layer, lies beneath the renal capsule. produce mineralocorticoid hormones like aldesterone which is controlled by the RAAS system which is controlled by the distal renal tubule.
what does aldesterone do
acts directly on renal tubules to increase sodium and increase water retention. this increases extracellular fluid volume and therefore increases arterial blood pressure
what is the zona fasciculata
middle and widest zona of the adrenal cortex. produces gluocorticoids, mainly cortisol which is stimulated by adrenocorticotropic hormone in times of stress. also secretes weak androgens
what is the zona reticularis
innermost layer of the adrenal cortex that produce precursor androgens like cholesterol
