C9: Adrenal Glands

Question 1

the adrenals are composed of what 2 parts?

these 2 parts develop from which cells?

Answer 1

1. Cortex
   - develop from mesoderm
2. Medulla
   - from neural crest cells/neuro-ectoderm

Question 2

which part of the adrenal develops first

Answer 2

cortex

Question 3

during cortical development, what occurs at 6 wks gestation

Answer 3

• proliferation of the mesoderm from the post abdo wall

- the proliferated mesoderm penetrates the retroperitoneum and becomes the primitive adrenal cortex

Question 4

during cortical development, what occurs at 8 wks gestation

Answer 4

-structure separates from the post peritoneal surface and is surrounded by retroperitoneal c-tissue which forms the adrenal capsule

Question 5

whats happening in terms of cortical development shortly after birth

Answer 5

-primitive adrenal cortex disappears by age 1

Question 6

whats happening in terms of cortical development at age 3

Answer 6

permanent adrenal cortex differentiates into 3 zones/layers

1. glomerulosa
2. fasciculata
3. reticularis

Question 7

during medullary development, what occurs at 7 wks gestation

Answer 7

-neural crest cells migrate and invade the medial side of the cortex and then differentiate into chromaffin cells of the medulla

Question 8

where do the neural crest cells develop?

Answer 8

outside the cortex, then migrate in

Question 9

another name for adrenals

Answer 9

suprarenals

Question 10

whats the relationship of the adrenals to the kidneys

Answer 10

anterior, medial and superior

Question 11

what fascia and fat surround the adrenals

Answer 11

• gerotas fascia

- perinephric fat

Question 12

do the adrenals have there own fascicle supports?

do they move with the kidney

Answer 12

yes… they move independent of the kidney

Question 13

what the norm size of the adrenals in adults

Answer 13

L: 4-6 cm
W: 2-3 cm
AP: 0.3-0.6 cm

1/13 of the kidney size

Question 14

what the norm size of the adrenals in kids

Answer 14

L: 0.9-3.6 cm
W: 0.2-0.5 cm

1/3 of kidney size

Question 15

which adrenal is usually largest

Answer 15

L

Question 16

whats the relationship of the R adrenal to the liver and curs of the diaphragm

Answer 16

• post to L lobe liver and medial to R lobe of liver

- lateral (for R and L adrenal)

Question 17

can the inferior border of the L adrenal extend to the renal hilum

Answer 17

yes

Question 18

whats the relationship of the L adrenal to the stomach and lesser sac

Answer 18

posterior

Question 19

whats the relationship of the inferior part of the L adrenal to the pan tail and splenic vessels

Answer 19

posterior

Question 20

if there was a mass on the L adrenal, how would that effect the pan tail

Answer 20

would push it anterior

Question 21

name the 3 arteries the supple each adrenal gland and where do they branch from

Answer 21

1. superior suprarenal artery (from inferior phrenic arteries)
2. middle suprarenal artery (from AO)
3. inferior suprarenal artery (from renal artery)

Question 22

how is blood drained from the adrenals and where does it drain into

Answer 22

suprarenal veins

R (short): drains into IVC
L (long) : drains into LRV

Question 23

what kind of gland is the adrenal often described as?

whats its general function and how does it accomplish it

Answer 23

double endocrine gland

-maintains homeostasis through hormone secretion

Question 24

what %. of the gland does the cortex make up?

is the adrenal cortex (AC) essential to life

Answer 24

90%

yes

Question 25

in general, what type of hormones does the cortex release? what type of system regulates the release of these hormones? list the specific hormones it releases

Answer 25

steroid hormones + regulated by - feedback system b/w the hypothalamus, anterior pituitary and adrenal gland - mineral corticoids - glucocorticoids - gonadal hormones

Question 26

describe how the - feedback system work to control the release of AC hormones

Answer 26

-blood level of adrenal cortex hormones are detected which causes the hypothalamus to secrete ACTHRF... ACTHRF stimulates the anterior pituitary to release ACTH which causes the cortex to produce hormones

Question 27

describe the the zona glomerulosa of the cortex. what does it secrete

Answer 27

- makes up 15 % of the cortex - outer layer + secretes mineralocorticoids... specifically aldosterone which acts on the renal tubule to increase sodium retention and increase BP

Question 28

describe the the zona fasciculate of the cortex. what does it secrete

Answer 28

- makes up 75 % of the cortex - middle layer + secretes glucocorticoids.... specifically cortisone and hydrocortisone which are for metabolism, suppress the immune response (anti-inflammatories) and helps resist mental and physical stress

Question 29

describe the the zona reticularis of the cortex. what does it secrete when does this zone become present

Answer 29

- makes up 10 % of the cortex - inner layer + secretes sex hormones.. specifically estrogen and androgens which promote development of reproductive organs and bones - @ 4 yrs

Question 30

the medulla is related to what nervous system in the body is it essential for life?

Answer 30

sympathetic nervous system... responsible for flight or fight not essential

Question 31

in general, what type of hormones does the medulla release? list the specific hormones it releases and there effect on the body

Answer 31

catecholamines -epinephrine/adrenaline + dilutes coronary vessels + constricts skin and renal vessels -norepinephrine + constricts all arteries except coronary vessels

Question 32

whats the body's response to catecholamines

Answer 32

- increases heart rate, BP (due to constriction), blood sugar, blood flow to muscles, respiration - dilates respiratory passages - slows digestions

Question 33

whats the purpose of performing a blood test for adrenal function

Answer 33

measures cortical function

Question 34

whats the purpose of performing a urine test for adrenal function

Answer 34

measures medulla function

Question 35

describe the echogenicity and echo texture of the adrenals in adults

Answer 35

homogenous and hypoechoic

Question 36

describe the echogenicity of the adrenals in kids when should child adrenals show and adult appearance

Answer 36

thin echogenic core (medulla) and less echogenic rim (cortex) -age 1

Question 37

why is it more difficult to see the adrenals in adults then children

Answer 37

they have more perirenal fat surrounding them

Question 38

which 4 structures can commonly mimic the adrenal glad on US

Answer 38

- crus of the diaphragm - panc tail - lymphadenopathy - gastric fundus

Question 39

whats the best way to interrogate the R adrenal where should the sound beam be directed if scanning the adrenal transversely

Answer 39

intercostally using liver of R kidney as a window... patient usually in supine + towards the IVC and should be scanning from the renal hilum to the liver

Question 40

whats the best way to interrogate the L adrenal whats an alternate way to scan the L adrenal

Answer 40

intercostal scanning using spleen or L kidney as a window... patient in decube or RAO - patient in LPO and scan through the liver, IVC and AO