Endocrine Histology Flashcards
Label these parts of the pituitary gland
A: hypothalamus
B: pituitary stalk
C: posterior pitiutary
D: anterior pituitary
Which one of these is AP and PP? [2]
Which part is AP and PP? [2]
Which part is AP and PP? [2]
The anterior part is derived from an upgrowth from the oral ectoderm of the primitive oral cavity called []
The anterior part is derived from an upgrowth from the oral ectoderm of the primitive oral cavity called Rathke’s pouch
Posterior pit. controlled by axons which nuclei in the hypothalamus? [1]
Anterior pit. controlled by axons which nuclei in the hypothalamus? [1]
Posterior pit. controlled by axons which nuclei in the hypothalamus? [1]
Paraventricular nuclei
Anterior pit. controlled by axons which nuclei in the hypothalamus? [1]
Supraoptic nucleus
What are the three types of cells in the AP? [3]
What are their differing roles?
Acidophil:
* Pink cytoplasm and dark nuclei
* Secrete protein hormones: growth factor and prolactin
Basophils
* Purple cytoplasm
* Secrete glycoprotein hormones: adrenocorticotrophic hormone,
thyroid stimulating hormone, follicle
stimulating hormone and luteinizing hormone
Chromophobe
* Non secretory serve as support or
precursors for acidophils and
basophils
What are the three types of cells in the AP? [3]
What are their differing roles?
Acidophil:
* Pink cytoplasm and dark nuclei
* Secrete protein hormones: growth factor and prolactin
Basophils
* Purple cytoplasm
* Secrete glycoprotein hormones: adrenocorticotrophic hormone,
thyroid stimulating hormone, follicle
stimulating hormone and luteinizing hormone
Chromophobe
* Non secretory serve as support or
precursors for acidophils and
basophils
What are the types of capillaries in the AP? [1]
The capillaries in this gland are fenestrated, to enable passage of hormones from the secretory cells into the bloodstream.
What are the two classes of acidophils?
What are the secretory products of these classes of acidophils? [2]
What are three classes of basophils? [3] and what are the secretory products? [3]
What are the two classes of acidophils?
Somatotrophs: GH
Mammotrophs: Prolactin
What are three classes of basophils? [3]
Gonadotrophs: FSH & LH
Thyrotrophs: TSH
Corticotrophs: ACTH
Which AP cells are which on the masson trichrome? [2]
Posterior Pit:
What are herring bodies and pituicytes in PP? [2]
- Herring bodies = focal axonal swellings packed with secretory granules
- Pituicyte = glial cells of the pituitary = nuclei that are visible
Explain the role of Pituicytes in the PP? [2]
Regulate the release of hormones: makes end feet (similar to astrocytes) that go around Herring bodies. When get release of signal - end feet retract & hormones go into blood
The [] portal circulation carries releasing hormones from the [] to the [] targeting the [] and [] and causing release of hormones into the blood stream.
the hypophyseal portal circulation carries releasing hormones from the hypothalamus to the adenohypophysis targeting the acidophils and basophils and causing release of hormones into the blood stream.
The bulk of the PP consists of axons from neurons in the [] and [] nuclei of the hypothalamus
The bulk of the PP consists of axons from neurons in the supraoptic and paraventricular nuclei of the hypothalamus
Label A of PP
Herring Bodies
What are different symptoms caused by microadenomas [1] and macroadenomas >1cm [1]
microadenomas: creates XS hormones
and macroadenomas >1cm: produce mass efects like headaches and visual disturbances
How do you tell which cells make up the pituitary adenoma? [1]
Appear the same: need to do immunohistochemical staining to tell the difference
How do you tell which cell class most commonly make up pituitary adenomas? [2]
- Somatotroph: GH
- Lactotroph: prolactin
Adrenal cortex secretes hormones made from which molecule? [1]
Cholesterol
What are the 3 divisions of the adrenal cortex? [3]
- Glomerulosa (near capsule)
- Fasiculata
- Reticularis (near medulla)
How do you ID the three different adrenal cortex cell layers? [3]
Zona glomerulosa: outer layer, purple, ovoid clusters, seperated by capillaries
Zona fasciculata: lipid droplets; appear more white
Zona reticularis: innermost layer. stains intensly
Which adrenal cortex zone is this? [1]
What does it secrete? [1]
Zona fasciculata (tell by the lipid nature)
Secretes: glucorticoids such as cortisol
Which adrenal cortex zone is this? [1]
What does it secrete? [1]
Zona reticularis (dark staining)
secretes sex hormones: oestrogen and testosterone
Which adrenal cortex zone is this? [1]
What does it secrete? [1]
Zona glomerulosa: aldosterone
Label A-C
A: zona glomerulosa
B: zona reticularis
C: zona fasciculata
What do each of the following produce:
zona glomerulosa
zona fasciculata
zona reticularis
What do each of the following produce:
zona glomerulosa: aldosterone
zona fasciculata: cortisol
zona reticularis: oestrogen and testosterone
What are the cells of the adrenal medulla called? [1]
What do they produce? [1]
What are the cells of the adrenal medulla called? [1]
Chromaffin cells
What do they produce? [1]
catecholamines (adrenaline and noradrenaline)
Label A
Central vein
What shape are chromaffin cells?
Chromaffin cells are columnar in shape and rather basophilic. At higher magnification, they are seen to have a granular cytoplasm due to hormone-containing granules. They are arranged in clusters, usually around medullary veins, as seen below in an image of rabbit adrenal (H&E stain).
How would an adenoma affect adrenal cortex?
- Adenoma = a benign tumour of glandular
origin - e.g. increase in cortisol
How would an adenoma affect adrenal cortex?
- Adenoma = a benign tumour of glandular
origin - e.g. increase in cortisol
How can you tell the difference between which cells secrete adrenaline and noradrenaline in adenal medulla? [2]
N: darker
A: lighter
What is pheochromocytoma?
Name 3 symptoms
- Grows from the chromaffin cells
- Most are benign only about 10% metastasise
to other parts of the body - Very rare (8 people per 1 million) * Classic triad of episodic (in around 30%)
- Headaches
- Sweating
-
Tachycardia
due to increased adrenaline release - Fine granular cytoplasm can be deeply basophilic
- Granules are filled with catecholamines
- Nuclei round or oval with one or more nucleoli
What are the structural units of thyroid cells called? [1]
Describe their structure [1] and the cell types that make them [1]
Which cel type lies adjacent to principal cells? [1]
What are the structural units of thyroid cells called? [1]
Follicles: principle cells are secretory epithelial cells that are surrounded by BM and reticular CT
- Parafollicular cells (C-cells) lie adjacent to
principal cells
Label A1 and A2 B C
A1: Follicles
A2: colloid (and a central mass of follicles)
B: Follicular epithelial cells
C: LCT
Why do follicular epithelial cells change in shape and how does this occur? [2]
Follicular cells - are almost columnar in appearance in some regions, whilst elsewhere they have a low cuboidal appearance.
This is because in active glands, the follicles are smaller, and have reduced colloid - the cuboidal lining cells are relatively tall because they are actively making and secreting hormones - so packed full of ER and golgi.
Hypothyroidism = squamous or cuboidal Hyperthyroidism = columnar
What substance do parafollicular cells (C-cells) produce and what function does this cause? [2]
Secrete calcitonin: decreases Ca2+ levels
Colloid is an inactive precursor of [] and []
Colloid is an inactive precursor of T3 and T4
Explain what Graves disease is and what causes it? [2]
Which molecules does it caused to be raised / depressed?
Type of
hyperthyroidism:
Autoantibodies (which mimics TSH) cause increase agaisnt TSH receptor on follicular epithelial cells
Causes colloid to become depleted:
Increases levels of :
- T4 & T3
- Radioiodine uptake
Decreases:
- TSH
Explain what Graves disease is and what causes it? [2]
Which molecules does it caused to be raised / depressed?
Type of
hyperthyroidism:
Autoantibodies (which mimics TSH) cause increase agaisnt TSH receptor on follicular epithelial cells
Causes colloid to become depleted:
Increases levels of :
- T4 & T3
- Radioiodine uptake
Decreases:
- TSH
FYI
Normal Thyroid on left
Graves on right: Clear vacuoles in colloid next to epithelium where increased activity of epithelium has used colloid to make thyroid hormone
Explain characterisitcs of Hashimoto thyroidosis
- Autoimmune disease of T
- Causes hypothyrodism due to destruction of TSH receptor
- Lympocyte infiltration occurs
What are two types of cells in parathyroid gland? [2]
What are their functions? [2]
How can you tell apart
What are two types of cells in parathyroid gland? [2]
Oxyphil cells function unknown, large, fewer, small acidophilic cytoplasm with many mito
Chief cells: produce PTH, prominent central nuclei surroundered by pale cytoplasm
A: chief cells
B: oxyphil cells
Identify the clusters of chief cells (CC), which secrete PTH. Also, identify oxyphil cells (OC), which are larger and paler staining than the chief cells.
What is the role of D-cells in islet of langehans? [1]
What is the role of D-cells in islet of langehans?
Produce somatostatin broad effects on gastrointestinal function, inhibits insulin and glucagon secretion
Where do you find alpha cells, beta cells and delta cells in islet of Langerhans?
Alpha: periperhy
Beta: Centre
Delta: scattered
Where do you find alpha cells, beta cells and delta cells in islet of Langerhans?
Alpha: periperhy
Beta: Centre
Delta: scattered
