Week 2: Adrenal Glands

Question 1

blood supply to adrenal gland

Answer 1

3 ARTERIES
1. inferior phrenic arteries->superior adrenal arteries
2. aorta-> middle adrenal arteries
3. renal arteries->inferior adrenal arteries
VESSEL SYSTEM
1. capsular capillaries: supply capsule
2. Fenestrated cortical capillaries that supply the cortex and then drain into fenestrated medullary capillary sinusoids
3. medullary arterioles: traverse cortex and bring blood to medullary capillary beds without giving blood to cortex

Question 2

Zona glomerulosa

Answer 2

• 15% of cortical volume

- closely packed ovoid clusters of cells

Question 3

Zona faciculata

Answer 3

• thick middle zone, 80% of cortical volume
• large polyhedral cells, long parallel cords, separated by fenestrated capillaries
• numerous lipid droplets
• lots of see, mitochondria, golgi

Question 4

Zona reticularis

Answer 4

• small cells, dark nuclei. Eosinophilic
• well developed see, numerous mitochondria
• secrete DHEA and DHEAS, converted to testosterone or estradiol in target tissue
• DHEA and DHEAS increase before puberty, resulting in growth of axillary and pubic hair: adrenarche

Question 5

adrenal medulla

Answer 5

• basophilic staining, more RER
• large pale staining epithelia cells called chromaffin cells
• dense core, membrane bounded secretory granules that secret NE
• less dense granules secrete Epi
• preganglionic sympathetic nerve fibers stimulate cells of medulla
• receives dual blood supply. Medullary cells that are exposed to glucocorticoids from the cortical sinusoids: GCs induce the enzyme that converts NE to epic.
• cells that receive blood rom medullary arteriole, with no exposure to GCs, produce NE