Endocrine anatomy Flashcards
Where is the pituitary gland located?
The pituitary gland is located in a depression of the sphenoid bone known as the hypophyseal or pituitary fossa
What covers the pituitary fossa?
A shelf of dura known as the sellar diaphragm
What structure passes through the sellar diaphragm and connects the pituitary gland to the base of the brain?
The infundibulum, or pituitary stalk
What are the missing labels?
What are the missing labels?
What are the magnocellular neurones?
Magnocellular neurons (MCN) are neuroendocrine cells located in the hypothalamus; they are among the largest cells in the brain, and synthesise the hormones arginine vasopressin (AVP) and oxytocin (OT)
Where are the cell bodies, axons and synapses of the magnocellular neurons located?
- Cell bodies: Supraoptic and Paraventricular nuclei of the hypothalamus
- Axons: Travel in the pituitary stalk
- Synapses: Posterior Pituitary
Where do the hormones oxytocin and vasopressin specifically originate from?
Oxytocin- from the cells which originate from the PVN
Vasopressin- from the cells which originate from the SON
What hormones are made in the anterior pituitary?
Adrenocorticotropic hormone, luteinising hormone, follicle stimulating hormone, thyroid stimulating hormone, growth hormone, prolactin.
How is the release of anterior pituitary hormones controlled?
Inhibitory and releasing hormones are made in the hypothalamus and transported to the anterior pituitary in a system of small blood vessels known as the pituitary portal system.
What structure is located immediately below the pituitary fossa?
The sphenoid sinus
What are the missing labels on this x-ray?
Where is the pituitary gland located?
What are the missing labels?
What are the different parts of the thyroid gland?
What are the missing labels?
What are the missing labels?
What are the missing labels?
What nerve do the superior and recurrent laryngeal nerves both originate from?
The vagus (CN-X)
What hormone(s) are released by the thyroid gland and how is the release of these controlled?
T3, T4, Calcitonin
The release of thyroid simulating hormone from the anterior pituitary controls the release of these
Where would you expect to find the parathyroid glands and what hormone do these produce?
On the posterior aspect of the thyroid gland- parathyroid hormone
What nerve is vulnerable to damage during thyroid surgery?
The recurrent laryngeal nerve
What does the recurrent laryngeal nerve innervate?
The recurrent laryngeal nerve provides sensory information below the vocal folds, and innervates all but one of the intrinsic muscles of the larynx, including cricoarytenoid, the only muscle to abduct the vocal folds
Where the thyroid gland recieve its blood supply from?
The superior thyroid artery (STA) arising from the external carotid artery (ECA), and the inferior thyroid artery (ITA) branching from the thyrocervical trunk which is a branch of the subclavian
What are the missing labels?
Which veins do the thyroid veins drain in to?
- Superior and middle thyroid veins – to internal jugular vein
- Inferior thyroid veins – to the brachiocephalic veins.
What is the blood supply to the parathyroid glands?
Primarily branches from the inferior thyroid arteries, collateral supply from superior thyroid arteries.
What are the missing labels?
What are the missing labels?
What are the missing labels?
What is the exocrine role of the pancreas?
Produces digestive enzymes which are secreted into the duodenum
The pancreas has an endocrine role. What hormones does it produce?
Insulin, glucagon and somatostatin
What arteries does the pancreas recieve its blood supply from?
From the celiac trunk:
- Splenic artery (which gives rise to the great pancreatic artery)
- Common Hepatic artery, which gives rise to the gastroduodenal, which in turn gives rise to the anterior and posterior superior pancreaticoduodenal arteries.
From the Superior Mesenteric
- Inferior pancreaticoduodenal arteries
What are the missing labels?
What are the missing labels?
What are the missing labels?
What are the missing labels?
What are the area between the anterior and posterior pituitary lobes that is void of any cells?
Notice that between these two parts there is an area which is devoid of any cellular elements – it forms a cleft between the two lobes. This is the pars intermedia, which is poorly developed in humans and a remnant of Rathke’s pouch from which the anterior lobe of the pituitary gland was formed.
What are the missing labels (pituitary gland)?
What are the differences between the chromophobes and chromophils in the anterior pituitary gland?
In the anterior pituitary, notice the glandular cells – chromophils which are split into acidophils and basophils (stain strongly due to the presence of secretory granules) and chromophobes (lack stainable cytoplasmic secretory granules)
What do acidophils, basophils and chromophobes look like in histology?
What are the missing labels in this histology of the pancreas?
What does a pancreatic islet look like in histology?
A high magnification of a pancreatic islet surrounded by acinar cells:
What is the function of the cells labelled b (parathyroid gland)?
Chief cell or principle cell
To secrete parathyroid hormone
To regulate blood calcium levels
What are the different cells in this hyroid gland?
F= follicle
S= septa
What are the missing labels on this parathyroid gland?
What does a thyroid follicle look like at high magnification?
C: Coloid (stored thyroglobin)
Note the ring a of single layer of cuboidal epithelial cells around the periphery of the follicle
What are the red and blue circles?
Red= pituitary/hypophyseal fossa
Blue= sphenoid sinus
What are Herring bodies and what do they look like?
Herring bodies- end of axons from hypothalamus in posterior pituitary -where hormone is released from
What is the blood supply to the pituitary?
Pituitary gets blood supply from superior and inferior hypophyseal artery (branches of the internal carotid artery)