Micro of Endocrine Glands - adrenal (suprarenal glands)

Question 1

Gross anatomy of adrenal glands

Answer 1

1. Next to kidneys
2. Capsule - can’t be peeled off
3. Cortex - outer
4. Medulla - inner

Question 2

Embryology of adrenal gland

Answer 2

• Cortex - derived from intermediate mesoderm
• Medulla - derived from neural crest cells (ectoderm)

Question 3

Capsule of adrenal gland is made of…

Answer 3

Dense irregular connective tissue

Question 4

Cortex contains three zones:

Answer 4

1. Zona glomerulosa (=arcuata)
2. Zona fasciculata
3. Zona reticularis

Question 5

Zona glomerulosa (=arcuata)

Answer 5

1. Cells exist in clusters that resemble glomeruli (glomerulosa), or in arches (arcuata)
2. Ultrastructure of steroid secreting cell - a lot of smooth ER
3. Mitochodnria with tubular cristae

Question 6

Zona fasciculata

Answer 6

• Cords of cells
• Cells contain lipid droplets
• Ultrastructure of steroid secreting cell - a lot of smooth ER

Question 7

Zona reticularis

Answer 7

• Network of cells
• Rows of cells from zona fasciculata break up as you get closer to medulla and get irregular
• Similar to cells of zona fasciculata

Question 8

Anatomy of medulla of adrenal gland

Answer 8

• Innervated only by sympathetic preganglionic neurons (modified sympathetic glangion) because the cells of the medulla, that arised from neural crest ectoderm are essentially modified sympathetic postganglionic neurons
• Cells sometiems called chromaffin cells because they have affinity for chromium salts (brown color)
• Two cell types: epinephrine cells and norepinephrine cells

Question 9

Function of cortex

Answer 9

1. Zona glomerulosa (arcuata) - produces mineralocorticoids (aldosterone)
2. Zona fasciculata - produces glucocorticoids (cortisol)
3. Zona reticularis - produces androgens in both males and females

Question 10

Function of medulla

Answer 10

Epinephrine and norepinephrine secretion stimulated by acetylcholine from sympathetic preganglionic neurons