Adrenal Glands Flashcards
What are the two parts that the adrenal glands are composed of
Cortex
Medulla
What does the medulla of the adrenals develop from
Neural crest cells
What is another name for neural crest cells
Neuroectoderm
What does the cortex of the adrenal glands develop from
Mesoderm
What part of the adrenal develops first
Cortex
At 6 week gestation what happen to the cortex
Proliferation of the mesoderm from the posterior abdominal wall occurs
Mesoderm penetrates the retroperitoneum and becomes the primitive adrenal cortex
At 8 weeks gestation what happens to the cortex of the adrenal glands
Structure separates from the peritoneal surface and is surrounded by retroperitoneal connective tissue
After birth what happens to the primitive cortex of the adrenal glands
Involuted and disappears around 1 year of age
At 3 years of age what happens to the permanent adrenal cortex
Differentiates into 3 zones
What are the 3 zones that the permanent adrenal cortex differentiates into
Glomerulosa
Fasciculata
Reticularis
What happens to the adrenal medulla at 7 weeks gestation
Neural crest cells migrate and invade the medial side of the cortex
These cells differentiate into the chromaffin cells of the adrenal medulla
What is another name for the adrenal glands
Suprarenal glands
What is the location of the adrenals
Retroperitoneal
Are adrenals paired organs
Yes
What is the location of the adrenals relative to the kidneys
Anterior
Medial
Superior
What are the adrenals surrounded by
Perinephric fat
Gerotas fascia
Do adrenals have a capsule
Yes
Do the adrenal move with the kidneys and how are they suspended
No, suspended by their own facial supports
What happens to the adrenal and the kidneys during deep inspiration or when sitting upright
Separate
What are adrenals composed of
Anteromedial ridge and a medial and latera wing
In an adult what is the size of the adrenals
Length: 4-6 cm
Width: 2-3 cm
AP: 0.3-0.6 cm
The size of adult adrenals is what of the kidney size
1/13
What is the size of newborn adrenals
Length: 0.9-3.6 cm
Width: 0.2-0.5 cm
What size of newborn adrenals is what to their kidneys
Proportionately larger
1/3 the kidney size
What is the shape of the adrenals
Pyramid
Semi-lunar
V/Y/Z configuration
What is the shape of the right adrenal
Pyramidal
What is the shape of the left adrenal
Semilunar
Crescent shaped
Which adrenal is usually slightly larger
Left
What are the relationships of the right adrenal relative to abdominal anatomy
Posterior and lateral to the IVC Superior to right kidney Posterior and medial to the liver Lateral to the right crux of the diaphragm Posterior to the duodenum
What are the relationships of the left adrenal relative to abdominal anatomy
Superomedial to the left kidney
Posterior to the stomach and lesser sac
Lateral to the left crux of the diaphragm
Inferior portion is posterior to pancreatic tail and splenic vessels
Posterolateral to the aorta
What kind of organ is the adrenals
Vascular
What boarder of the left adrenal can reach the renal hilum
Lower
What 3 arteries supply each adrenal
- Superior suprarenal arteries from the inferior phrenic arteries
- Middle suprarenal artery off the aorta
- Inferior suprarenal artery off the renal artery
What is the venous drainage of the right adrenal
Drains into the IVC
Shorter than left adrenal vein
What is the venous drainage of the left adrenal
Drains into the left renal vein
Longer than right adrenal vein
What kind of gland are the adrenals
Double endocrine
What does a double endocrine gland do
Maintains homeostasis through hormone secreation
what are the 2 layers of the adrenals
cortex
medulla
what makes up 90% of the adrenal
cortex
what kind of outer layer does the cortex have
thicker
what hormones does the cortex secrete
mineral corticoids
glucocorticoids
gonadal hormones
what part of the adrenal is essential for life
cortex
can you have 1 functioning adrenal cortex and not 2, is having none fatal for life
yes
how is the release of steroid hormones controlled
by negative feedback system between the hypothalamus, anterior pituitary and adrenal gland
what does the hypothalamus secrete
ACTHRF
what does ACTHRF stand for
adrenocorticotropic hormone releasing factor
what does the cortex cause the anterior pituitary to release
ACTH
what does ACTH stand for
adrenocorticotropic hormone
what does the cortec cause the adrenals to do
produce hormones
what are the 3 layers of the cortex
zona glomerulosa
zona fasciculate
zona reticularis
what is the zona glomerulosa and what percentage of the cortex does it make up
15%
outer most layer
secretes mineralocorticoids
aldosterone
what does aldosterone do
acts on renal tubules for sodium and water retention by the body so it can assit in raising and lowering BP
what is the zona fasiculate and what percentage of the cortex does it make up
75%
middle layer
secretes glucocorticoids
what are the glocorticoids that the adrenal cortex secretes and what do they control
cortisone and hydrocortisone control: fat, protein and carbohydrate metabolism suppresses immune response (anti-inflammatory) helps resit mental and physical stress
what is the zona reticularis and what precentage of the cortex does it make up
10%
inner most layer
secretes sex hormones
what are the sex hormones that the adrenal cortex secretes and what do they control
estrogen and androgens
promotes normal development of the reproductive organs and bones
when is the zona reticularis present
around the 4th year of life
what makes up 10% of the adrenal layers
medulla
what is the position of the medulla
central
what is the medulla related to and where is it derived from
sympathetic nervous system
ectoderm
is the medulla essential for life
no
what response is the medulla responsible for
fight or flight
what does the medulla secrete
catecholamine hormones
what catecholamine hormones does the medulla secrete
epinephrine
norepinephrine
what does epinephrine do
dilates cononary vessels
consricts skin and renal vessels
what does norepinephrine do
constircts all arteries except coronary vessels
