Adrenal glands and gonads 29 Flashcards
Where are adrenal glands found?
Superior to the kidneys.
What are the adrenal glands made up of?
85% adrenal cortex, 15% adrenal medulla (neural tissue)
There are 3 zones in the cortex-3 steroid hormones, what are they?
1) Outer zone - mineralocorticoids - mineral homeostasis
2) middle zone - glucocorticoids - glucose homeostasis
3) inner zone - androgens - steroid masculinising hormones
What is the major form of mineralocorticoids?
Aldosterone is the major form.
What does aldosterone do?
Regulates mineral & water balance by action on kidneys.
What do mineralocorticoids stimulate?
Na+ reabsorption from urine to blood,
Excretion of k+ into urine.
What does inhibin do?
inhibits FSH
what is produced from ovaries and testes.
gametes and sex steroids.
what are oestrogen and progesterone required for?
sexual characteristics, menstrual cycle, pregnancy and lactation.
what cells does the adrenal medulla consist of, what is it stimulated by and what does it release?
consists of sympathetic post ganglionic cells.
stimulated by preganglioic sympathetic neurons
releases epinephrine and norepinephrine.
what do androgens do?
stimulates axillary hair growth, contributes to female libido, adolescent growth spurt and are converted to oestrogens in other body parts.
what do glucocorticoids do?
increase protein breakdown.
breakdown triglycerides in adipose tissue,
anti-inflammatory effects.
depresses immune system.
what are glucocortisoids regulated by?
negative feedback through hypothalamus.