Microanatomy of the adrenal glands

Question 1

Zones of the adrenal cortex

Answer 1

• Zona glomerulosa (aldosterone): thin outer layer, consisting of closely packed ovoid clusters and curved columns, a fairly pale layer
• Zona fasciculata (cortisol): thick middle zone consisting of polyhedral cells arranged in long parallel cords separated by fenestrated capillaries, is even paler than the glomerulosa
• Zona reticularis (androgens): thin deep layer w/ small cells and dark nuclei arranged in anastomosing cords and separated by capillaries, is very eosinophilic

Question 2

Adrenal medulla

Answer 2

• Basophilic area (deepest part) composed of ovoid cells and short interconnecting cords of large epithelioid (chromaffin) cells which are pale
• Secretes epi and NE

Question 3

Blood supplies to adrenal gland

Answer 3

• Cortical capillaries run through the cortex and pick up cortisol, then epi/NE
• Medullary arterioles bypass the cortex and only pick up epi/NE (medullary capillaries will NOT have cortisol)