Suprarenal Glands Week 1 FINISHED Flashcards
Are the suprarenal glands endocrine or exocrine?
Endocrine
Where do endocrine glands secrete their hormones?
Directly into the blood stream
Where do exocrine glands secrete their hormones?
Through a duct onto an epithelial surface of the organ e.g. sebaceous glands or sweat glands
Where do the suprarenal glands lie?
Superior and anterior to the superior pole of each kidney
At what level in the body are the suprarenal glands?
Approx T12
Where are the suprarenal glands found in relation to the diaphragm?
They are found between the superior and medial surface of each kidney and the diaphragm
Are the suprarenal glands symmetrical?
No
What colour are the suprarenal glands?
Yellowish
What surrounds the suprarenal glands?
Connective tissue and perinephric fat, within their own compartment of the renal capsule.
What is the shape of the right suprarenal gland?
Pyramidal/triangular in shape
What organs/structures is the right suprarenal gland in contact with/surrounded by?
The anterior surface is overlapped medially by the IVC.
The rest of the anterior surface is in contact with the liver.
Are the suprarenal glands peritoneal or retroperitoneal?
Retroperitoneal
What is the shape of the left suprarenal gland?
Cresent/semi lunar
What other organs does the left suprarenal gland have contact with?
Spleen, stomach and pancreas
What distance from each other are each of the medial borders of the suprarenal glands?
4-5cm
What is found between the suprarenal glands from right to left?
IVC, right crus of the diaphragm, coeliac ganglion and trunk, SMA, left crus of the diaphragm
What is the arterial supply of the suprarenal glands?
Branches of the:
- inferior phrenic arteries,
superior suprarenal arteries (6-8) - aorta, (near the level of the SMA)
middle suprarenal arteries (1+) - renal arteries,
inferior suprarenal arteries (1+)
What is the venous drainage of the suprarenal glands?
One vein from each gland:
The left drains into the left renal vein and is slightly longer than the vein to the right suprarenal gland which drains directly into the IVC.
What is the nerve supply for the suprarenal glands?
SNS: Splanchnic nerves via and coeliac plexus, T10-T11
PSNS: NO Parasympathetic supply
What is the structure of the suprarenal glands?
They have a cortex and a medulla, which are made from 2 different kinds of endocrine tissue. The Medulla is made from ectoderm and the cortex is made from mesoderm.
What is the function of the cortex of the suprarenal glands?
Secretes a variety of steroid hormones which are all structurally related to cholesterol.
What is a hormone?
A substance which is produced in one part of the body, passes into the blood stream and is carried to other distant organs or tissues where is modifies their structure or function
What is a steroid?
A group of compounds having a common structure based on the steroid nucleus which consists of 3 six membered carbon chains and 1 five membered carbon chain.
How many layers does the cortex of the suprarenal glands have?
3
Steroid hormones secreted by the cortex of the suprarenal glands are typically divided into 3 subcategories which are:
Mineralcorticoids
Glucocorticoids
Sex Hormones
What is the function of mineralcorticoids?
Usually concerned with fluid and electrolyte metabolism
Are necessary for the regulation of salt and water balance
What is the function of glucocorticoids?
Have a wide range of effects on carbohydrate, lipid and protein metabolism
What is the function of sex hormones?
Supplements the gonadal sex hormone secretion
What are the 3 layers of the cortex of the suprarenal gland? Describe each of the layers in terms of how they appear
Outermost layer = Zona glomerulosa (small rounded cells found in clusters)
Middle layer = Zona fasciculata (parallel rows of pale staining vacuolated cells. these parallel rows are found at right angles to the capsule)
Innermost layer = Zona reticularis (network of smaller dark staining cells. Arranged in irregular cords)
What does the zona glomerulosa of the cortex of the suprarenal gland secrete?
Mineralcorticoids
What does the zona fasciculata of the cortex of the suprarenal gland secrete?
Glococorticoids
What does the zona reticularis of the cortex of the suprarenal gland secrete?
Sex hormones
What are the principle products of the cortex of the suprarenal gland and what are they effects on the body?
Cortisol, aldosterone and androgens
They cause the kidneys to retain water and sodium in response to stress, increase blood pressure and blood volume, affect muscle and organs such as the heart and lungs.
What part of the nervous system directly controls the medulla?
The sympathetic nervous system
What is the function of the medulla of the suprarenal gland?
It reinforces the action of the SNS under conditions of stress.
What does the medulla of the suprarenal gland look like?
Innermost to the cortex, it is thinner, smaller and grey
What do the cells of the medulla of the suprarenal gland do?
They secrete catecholamines:
- adrenaline (epinephrine)
- noradrenaline (norepinephrine)
- dopamine
These increase heart rate, increase blood pressure and dilate bronchioles, activating the bodes flight or fight response.
Where in the suprarenal gland are dilated capillaries usually found?
In the medulla but not usually the cortex.
