Glomerular, Fascicular, Reticular. [Also called, zona Glumerulosa, zona Fasciculata, and zona Reticulata]
- Zona reticularis - sex hormones (androgens in men, oestrogen & progesterone in women)
- Zona fasciulata - glucocorticoids (cortisol/hydrocortisone, corticosterone & cortisone)
- Zona glomerulosa - mineralocorticoids (aldosterone)
Medulla part -
A) sympathetic NS
b) contains chormaffin cells - specialised sympathetic post-ganglionic neurons
c) nerve fibres from splanchnic nerve innervate -> release acetylcholine
-> hormone release
d) Produces
- adrenaline
- noradrenaline
- dopamine
- b- hydroxylase (enzyme in catecholamine synthesis)
- ATP
- opiod peptides
Adrenal gland embryology
- 1st detected?
- derived from which _derm
at 6 weeks gestation
mesoderm of posterior abdo wall
steroid secretion from cortex begins shortly after
Adrenal gland embryology
- which type of zones fetal/adult
- progression / transition time
- fetal cortex predominates throughout fetal life
- adult type: z.glomerulosa and fasciculata detected but small portion, z.reticularis not present
rapid regression of fetal cortex - 4 months (4xtimes kidney) -> birth (kidney's size), 1 year almost disappears, by 4-5 - permanent adult type adrenal cortex
embryological origin of adrenal medulla
Ectoderm
Arising from neural crest cells that migrates to medial aspect of dev cortex
Adrenal gland - anatomic anomalies
- closely related to ?
- 2 conditions
to development of kidneys
- agenesis of adrenal gland - ass. w/ ipsilateral agenesis of kidney
- fused adrenal glands (joining across midline, post to aorta) - ass. w/ fused kidney
Anomalies of adrenal gland
- hypoplasia
- heterotopia (abnormal displacement)
- accessory adrenal tissue
2 forms of adrenal hypoplasia
1) hypoplasia/absence of fetal cortex with a poorly formed medulla
2) diorganised fetal cortex and medulla with no permanent cortex present
adrenal heterotopia
a normal adrenal gland in an abnormal location, such as within the renal or hepatic capsules.
Accessory adrenal tissue
- also called?
- usually comprised of?
- located?
- adrenal rests
- usually comprised only of cortex but seen combined with medulla in some cases
- most commonly located in the broad ligament or spermatic cord but can be found anywhere within the abdomen, even intracranial adrenal rests
Hormone secretions - Products of the adrenal cortex, from outer to inner layer
Salt, sugar, sex; “the deeper you go, the sweeter it gets.”
Salt = aldosterone, sugar = glucocorticoids (cortisol), sex = sex hormones (androgens)
Zona reticularis - sex hormones (androgens in men, oestrogen & progesterone in women)
- Zona fasciulata - glucocorticoids (cortisol/hydrocortisone, corticosterone & cortisone)
- Zona glomerulosa - mineralocorticoids (aldosterone)
Medulla secretion
The Medulla
The adrenal Medulla secretes stress hormones Epinephrine and Norepinephrine in response to stress in MEN ( Medulla – Epinephrine – Norepinephrine make the acronym MEN)