Adrenal gland anatomy Flashcards
What do the adrenal glands produce?
Produce adrenaline or epinephrine (US version), and also known as suprarenal gland
Where are the adrenal glands located?
Location: Medial to cranial pole of kidney although there are some species variation.
What structures surround the adrenal glands?
Related structures: Kidney, caudal vena cava, aorta and renal artery and vein
What are the two gross zones of the adrenal gland?
Cortex
Medulla - modified nervous tissue
What are the three layers of the cortex? What do they produce?
Zona glomerularis (outer)= Mineralocorticoids.
Zona fasciculata (middle)= Glucocorticoids.
Zona reticularis (inner)= Oestrogen, Testosterone, (some progesterone).
What does the medulla produce?
Adrenaline and noradrenaline
Where does the cortex of the adrenal gland come from?
Cortex from mesoderm between gonadal ridge and mesentery.
Cranial end of the mesonephros.
Where does the medulla of the adrenal gland come from?
Medulla from neural crest cells that produce the sympathetic gangli
In the fetus which part of the adreanal gland develops first and why? What is the exception?
Fetal cortex develops first: Produces corticosteroids in all species and converts placental progesterones to androgens.
In equidae the gonads perform this task. Hence large gonads in fetal equidae.
Regresses after birth as adult cortex develops.
How does the adult adrenal cortex take over the fetal one?
The foetal cortex regresses after birth and is enveloped by the adult cortex which grows after birth to replace the fetal cortex.
What is happening to the medullary cells at birth?
Medullary cells are still migrating at birth, so can be found in extra-cortical sites
What is the innervation to the adrenal gland?
Fibres to the adrenal medulla are preganglionic as the medulla is essentially post ganglionic neural cells
