SFP: adrenal glands Flashcards
Describe the shape of the left adrenal gland
Crescent shaped and along the medial aspect of the kidney
Describe the shape of the right adrenal gland
Pyramid shaped and only of the superior aspect of the kidney
The right adrenal gland is posterior to…
The IVC
Each adrenal gland receives blood from which arteries?
Superior adrenal from the phrenic, middle adrenal for the aorta, and inferior adrenal from the renal
The left adrenal vein drains to…
The left renal vein
The right adrenal vein drains to…
The IVC
What does the cortex of the adrenal gland produce?
Mineral corticoids, glucocorticoids, and androgens
What does the medulla of the adrenal gland produce?
Epi and norepi
What germ cells does the cortex come from?
Mesoderm
What germ cells does the medulla come from?
Neural crest
What is true of fetal adrenal glands in terms of size?
They’re comparatively much bigger! They’re about the same size of the kidney
Describe the basic structure of the fetal adrenal cortex
There’s an outer thin mantle layer that becomes the cortex as well as a central mass of transient cells that produce DHEA that converts to estrogen by the placenta
Where is sympathetic innervation of the adrenal cortex derived from?
The greater splanchnic nerve
Where in the cortex do sympathetic fibers synapse?
Pre-aortic or aortico-renal ganglia
Describe sympathetic nerve supply of the adrenal medulla
Fibers from the greater splanchnic nerve may pass to the medulla without synapsing at all. This is because the medulla originates from neural crest cells and is like a ganglion!
What are the histological regions of the cortex?
Zona glomerulosa, zona fasciculata, and zona reticularis
Describe the zona glomerulosa
Top layer composed of balls of cells
Zona glomerulosa is stimulated by __ and produces __
ang II, aldosterone
Describe the zona fasciculata
Bundles of cords of cells. This layer stains lighter than the others due to being steroid secreting cells. It is the largest layer
What are the characteristics of a steroid secreting cell?
- Large amounts of lipid vacuoles
- Smooth ER
- Mitochondria with tubular cristae
Zone fasciculata is stimulated by ___ and secretes ___
ACTH, cortisol
Describe the zona reticularis
Net-like organization of cells
Zona reticularis is stimulated by ___ and produces ___
ACTH, androgens
Where are chromaffin cells?
In the medulla; they secrete catecholamines and are arranged in cords beside capillaries and sinusoids
What is the origin of chromaffin cells?
Neural crest
Do chromaffin cells make more epi or norepi?
Epi
Larger granules in the adrenal medulla contain ___ and smaller granules contain ___
Norepi, epi
Describe the blood supply within the adrenal gland
Capsular arteries bring blood to the capsule of the gland. Cortical capillaries are located in the zona glomerulosa and reticularis and connected through the zona fasciculata. Blood flows through the artery, through the capillary beds, and to medullary capillaries and finally medullary veins. There is also a medullary arteriole that bypasses the capillary system to bring oxygen rich blood to the medulla
Describe how cortisol in the fasciculata gets to the medulla and why this is significant
It travels through the cortical and medullary capillaries, where it can activate PNMT used to convert norepi to epi
