Lab 1: Adrenal gland and endocrine pancreas Flashcards
Name the three zones of the adrenal cortex and the hormone produced from each of these areas
The adrenal medulla is also a site of hormone secretion: name its products?
Adrenaline and noradrenaline
The adrenal gland consists of three distinct parts. Name them
Adrenal cortex (outer)
Adrenal medulla (inner)
Surrounding fibrous capsule
The adrenal cortex is subdivided into three concentric zones.
Name them
- Zona glomerulosa (outermost)
- Zona fasciculate (middle)
- Zona reticularis (innermost)
Name these parts of the adrenal glands
Describe the anatomical arrangement of the cells in the zona glomerulosa
The cells are arranged into clumps that are surrounded by separated by trabeculae that are continuous with the capsule.
Describe the trabecula in the adrenal gland
The trabecula contain blood vessels that extend from the capsule into the cortex and to the medulla
What hormone does the zona glomerulosa cells produce
The outermost zone of the adrenal cortex secretes mineralcorticoids eg. aldosterone
These hormones are important for fluid homeostasis.
These include aldosterone, which regulates absorption/uptake of K+ and Na+ levels in the kidney.
Which zone is the biggest in the adrenal cortex
Zona fasiculata
Making up approx. 80% of the cortex
Describe the anatomical arrangement of the cells in the zona fasciculata
The cells are arranged in vertical columns/cords. The cords are surrounded by fine strands of supporting tissue
Describe how the cells of the zona fasciculata would look histologically
- Appear in columns
- The cells have considerably more cytoplasm than those of the other cortical zones and stain palely because of their high concentration of lipid droplets
What hormone does the zona fasciculate cells produce
Secretes glucocorticoids e.g. cortisol
Glucocorticoids are important for carbohydrate, protein and lipid metabolism.
Cortisol is the main one secreted, which raises blood glucose and cellular synthesis of glycogen. Its secretion is controlled by a hormone from the pituitary - ACTH.
What hormone does the zona reticularis cells produce
Secretes adrenal androgens (i.e sex hormones)
The cells forming the zona fasciculate appear pale in H&E stained section contain empty looking, small rounded profiles. Why? and what is the other name of these cells
The other name is spongiocytes.
Appear pale because of their high concentration of lipid droplets
This is an image of the adrenal gland which has been stained with a dye that labels lipids. Identify the heavily stained (dark) region and the hormone it produces.
Zona fasciculata as the cells here have a high lipid droplet concentration.
Hormone = cortisol.
What is the embryological origin of the cortex of the adrenal gland
Mesoderm
What is the embryological origin of the medulla of the adrenal gland
Ectoderm
The functions of the adrenal medulla are controlled by the ___ divison of the ___ nervous system
A) Sympathetic division
B) Autonomic nervous system
What are the 3 main arteries that supply the adrenal gland
Superior adrenal artery
Middle adrenal artery
Inferior adrenal artery
The right adrenal vein drains into
The inferior vena cava
The left adrenal vein drains into
Left renal vein
What are the main secreting cells of the adrenal medulla
Chromaffin cells, which are neuroendocrine cells that are modified sympathetic ganglia. The chromaffin cells are neural crest cell derivatives.
What hormone does the adrenal medulla secrete?
The chromaffin cells secrete adrenaline and noradrenaline
A patient has a tumour of the adrenal medulla.
Which hormone is likely to be in excess in the patient’s blood?
Adrenaline and noradrenaline
