Adrenal Gland Histology

Question 1

What does the cortex of the adrenal gland originate from?

Answer 1

Mesodermal

Develops from celomic epithelium of the posterior abdominal wall

Question 2

What does the medulla of the adrenal gland originate from?

Answer 2

Ectodermal

Develops from neural crest cells

Question 3

By the eight week of fetal development, the cortical elements have differentiated into what?

Answer 3

Thin outer definitive cortex and a thicker inner fetal cortexx

Question 4

What does the fetal cortex actively produce?

Answer 4

fetal steroids during gestation but involutes rapidly after birth

Question 5

What are adrenocortical rests?

Answer 5

Occur in up to 50% of newborn infants
Tend to atrophy and disappear early postpartum period
Can be found along path of embryonic migration of adrenal cortex

Question 6

Describe accessory adrenocortical nodules

Answer 6

minor developmental anomalies arising from partly or completely detached rests of the coelomic epithelial primordia from which the adrenal cortex is derived

Most frequently located in contact with the capsule at one pole of adrenal but can occur completely separated in the retroperitoneal fat

Question 7

Describe the development of adrenal zones

Answer 7

occurs slowly after birth, in parallel with regression of fetal cortex
Distinct zonae glomerulosa and fasiculata present at birth
Zona reticularis develops during the first year of life

Question 8

medullary elements, derived from __________, migrate forward to ________ and paravertebral regions and along the adrenal vein toward the medial aspect of the developing ___________.

Answer 8

Neural crests
para-aortic
adrenal fetal cortex

Question 9

During the early stage of gestation, the adrenal cortex synthesizes ____________, a precursor of the synthesis of estrogen by the _________.

Answer 9

dehydroepiandrosterone (DHEA)

Placenta

Question 10

A lack of ________________ activity prevents the synthesis of progesterone, glucocorticoids and androstenedione

Answer 10

3 beta-hydroxysteroid dehydrogenase (3B-HSD)

Question 11

The interactions between the fetal adrenal cortex and the placenta is known as the __________.

Answer 11

fetoplacental unit

Question 12

3B-HSD Congenital adrenal hyperplasia is an __________ form of CAH. It results from a mutation in the gene for ___________.

Answer 12

uncommon

3 beta- HSD type II

Question 13

What are the clinical presentations of 3 beta- HSD CAH?

Answer 13

Incomplete loss of 3 beta - HSD Type II

Virilization of genetically female infants and undervirilization of genetically male infants

Question 14

3B - HSD CAH is a form of ______ hypoadrenalism, and is the the only form of CAH that can cause___________ in both genetic sexes.

Answer 14

primary

Ambiguous genitalia

Question 15

During pregnancy, what are the sources of glucocorticoids for the fetus?

Answer 15

either of maternal origin or synthesized from placental progesterone by the fetus

Question 16

What are the three main developmental events that require glucocorticoids?

Answer 16

1. production of surfactant by type II alveolar cells after eight month of fetal life
2. development of functional hypothalamopituitary axis
3. induction of thymic involution

Question 17

Each gland consists of a _____ outer cortex (__%) and a _____ inner medulla (__%)

Answer 17

Yellowish
80-90%

Reddish
10-20%

Question 18

The adrenal cortex is of _______ origin and produces ______.

Answer 18

mesodermal

steroid hormones

Question 19

The adrenal medulla is of ________ origin and produces __________.

Answer 19

Neuroectodermic

Catecholamines

Question 20

The adrenal cortex consists of three concentric zones:

Answer 20

1. outermost layer of the cortex: zona glomerulosa
2. middle layer: zona fasiculata
3. innermost: zona reticularis

Question 21

What does the zona glomerulosa produce and to what stimulus ?

Answer 21

mineralocorticoids, mainly aldosterone

in response to Angiotensin II also ACTH

Question 22

Describe the histology of zona glomerulosa

Answer 22

lies under capsule and is 10-15% of cortex

cells aggregate into glomerulus-like arrangement and have a moderate amount of lipid droplets in the cytoplasm

Question 23

Zona glomerulosa lacks the enzyme ___________, cant produce sex steroids or _______.

Answer 23

17alpha-hydroxylase (CYP17)

cortisol

Question 24

Aldosterone stimulates the retention of ____, ______ in kidneys, and renal secretion of ____ and _____.

Answer 24

Na, H2O

K and H

Question 25

What does the zona fasiculata secrete?

Answer 25

glucocorticoids and androgens

Question 26

Describe the histology of zona fasiculata

Answer 26

75% of cortex cells contain many lipid droplets of cholesterol (precursor) in cytoplasm Cells appear vacuolated (foamy appearance) Spongiocytes Cuboid cells: steroid-producing cell arranged in longitudinal cords separated by cortical fenestrated capillaries/sinusoids

Question 27

The adrenal glands are highly vascularized. What are the aa that supply the glands?

Answer 27

Superior suprarenal aa - inferior phrenic a Middle suprarenal aa - abdominal aorta Inferior suprarenal aa - renal a

Question 28

What part of the adrenal cortex contains 17-alpha hydroxylase? What is it necessary for?

Answer 28

ZF and ZR | Necessary for production of glucocorticoids - cortisol

Question 29

What can be found in ZF and ZR that is required for the production of sex hormones?

Answer 29

17, 20-hydroxylase

Question 30

Cortisol (is/isnt) stored in cells of ZF and ZR. New synthesis is stimulated by ________.

Answer 30

isnt ACTH

Question 31

Cortisol is converted in __________ to cortisone

Answer 31

hepatocytes

Question 32

What are the two major effects of cortisol?

Answer 32

Metabolic effect: stimulates gluconeogenesis to increase the [glucose] in blood Anti-inflammatory effect: suppresses tissue responses to injury and decreases cellular and humoral immunity

Question 33

Zona fasciculata is often associated with ________ production

Answer 33

glucocorticoid - mainly cortisol

Question 34

The zona reticularis is often associated with ______ production

Answer 34

androgen

Question 35

Describe the histology of zona reticularis

Answer 35

innermost layer of the cortex: 5-10% of total volume Cells arranged in irregular cords that form an anastomosing network Secrete glucocorticoids and androgens

Question 36

What is the primary sight of adrenal sex hormone production?

Answer 36

zona reticularis, although cells of the zona F can synthesize androgens

Question 37

What are the predominant androgens produced by the cortex of the adrenal gland ?

Answer 37

DHEA aand androstenedione

Question 38

Although DHEA and androstenedione are weak androgen, they can be converted into what?

Answer 38

testosterone and even to estrogen in peripheral tissue

Question 39

The adrenal gland is the major source of _____ in women. What do they stimulate?

Answer 39

androgens | Stimulate the growth of pubic and axillary hair during puberty

Question 40

Describe Chromaffin cells

Answer 40

Composed of polyhedral cells arranged in cords or clumps Regarded as modified sympathetic postganglionic neurons without postganglionic axons Derived from neural crest Secretes EP, NE

Question 41

What did chromaffin cells lose during embryonic development?

Answer 41

axons and dendrites and become secretory cells Modified sympathetic postganglionic neurons w/o postgangionic axons

Question 42

What is the adrenal medulla innervated by?

Answer 42

sympathetic preganglionic fibers that release ACh

Question 43

How are catecholemines different from neurotransmitters?

Answer 43

Catecholamines are secreted into the blood instead of being secreted into a synapse

Question 44

Catecholemines are secreted in response to ___________ reactions. What are the effects?

Answer 44

intense emotional Defensive reaction to stress Increase heart rate Dilates blood vessels supplying cardiac and skeletal mm Bronchiole dilation Vasoconstriction of blood vessels supplying GI tract, kidneys, skin

Question 45

All three adrenal aa enter the adrenal gland capsule and for an ____________

Answer 45

arterial plexus

Question 46

What are the three sets of branches that emerge from the arterial plexus of the adrenal gland?

Answer 46

Subcapsular plexus Short cortical aa Long cortical aa

Question 47

What does the subcapsular plexus supply?

Answer 47

the capsule

Question 48

What does the short cortical aa supply? What is its pathway

Answer 48

enters the cortex forming straight fenestrated capillaries/sinusoids, percolating btwn the zonae glomerulosa and fasiculata, and forming a capillary network in the ZR before entering the medulla

Question 49

What does the long cortical aa supply?

Answer 49

Medullar aa travel w/o branching and supplying blood only to the medulla

Question 50

Medulla has direct blood supply from ________ as well as _______ from the cortex.

Answer 50

long cortical aa | Sinusoids

Question 51

What can a tumor in ZG cause?

Answer 51

excessive secretion of aldosterone | rare condition: primary aldosteronism/Conn's syndrome

Question 52

What is a more common cause of hyperaldosteronism?

Answer 52

increase in renin secretion: secondary hyperaldosteronism

Question 53

What is Cushing's disease caused by?

Answer 53

ACTH-producing tumor of the anterior hypophysis 70% of endogenous cases of cushings

Question 54

What hormone levels are expected in Cushing's disease?

Answer 54

increase in aldosterone, cortisol, adrenal androgen production

Question 55

What is Cushing's syndrome

Answer 55

A functional tumor of the adrenal cortex that results in overproduction of cortisol, as well as aldosterone and adrenal androgens 15% of endogenous cases of Cushings

Question 56

What are the exogenous causes of Cushings syndrome?

Answer 56

Taking medicines containing glucocorticoids, such as hydrocortisone

Question 57

What is Addison's disease?

Answer 57

a chronic destruction of adrenal cortex by an autoimmune process or tuberculosis Cortisol deficiency leads to ACTH secretion increase

Question 58

What are the clinical manifestations of Addison's disease?

Answer 58

Increase in skin pigmentation, in particular in the skin folds and gums due to ACTH increase Loss of Mineralcorticoids leads to hypotension and circulatory shock Deficient cortisol causes muscle weakness

Question 59

What are the signs of Addison's disease?

Answer 59

``` weight loss hyperpigmentation hypotension thinning of axillary and pubic hair vitiligo ```

Question 60

What are the symptoms of Addison's disease?

Answer 60

fatigue, anorexia, syncope, postural dizziness, nausea, vomiting, diarrhea, constipation, abdominal pains, myalgias, decrease libido

Question 61

What is pheochromocytoma?

Answer 61

Benign tumor of chromaffin cells 25% familial

Question 62

What occurs with pheochromocytoma?

Answer 62

Episodic secretions of EP and NE | Excessive catecholamine secretion ->hypertension or cardiac arrhythmias

Question 63

What are the signs and symptoms of pheochromocytoma?

Answer 63

SNS hyperactivity: elevated HR, BP, palpitations, diaphoresis, anxiety, headaches, nausea, pallor Hatfield-McCoy Feud: apparently von hippel-landau has pheochromacytomas that make you want to fuck ppl up