13. Endocrine glands (anatomy)

Question 1

Where does the pituitary gland sit?

Answer 1

In the sella turcica of the sphenoid bone
The sella turcica has bone anteriorly and posteriorly BUT not to the sides - so in a pituitary adenoma, the growth would be laterally outwards

Question 2

What is the infundibulum?

Answer 2

This is the pituitary stalk - the connection between the hypothalamus and the posterior pituitary

Question 3

How do the anterior and posterior lobes of the pituitary gland differ from each other?

Answer 3

The posterior lobe is a continuation of the hypothalamus - composed of neurones and is not a true endocrine gland
The anterior lobe is pinker in colour and is made up of endocrine secretory cells rather than neuronal cells

Question 4

What hormones are released from the anterior lobe of the pituitary gland?

Answer 4

Adrenocroticotrophic hormone (ACTH)
Thyroid-stimulating hormone (TSH)
Luteinising hormone (LH)
Follicle stimulating hormone (FSH)
Prolactin (PRL)
Growth hormone (GH)
Melanocyte-stimulating hormone (MSH)

Question 5

What hormones are released from the posterior lobe of the pituitary gland?

Answer 5

Anti-diuretic hormone (ADH)

Ocytocin

Question 6

Where do secretions of the pituitary gland drain to?

Answer 6

The hypothalamo-hypophyseal portal system

Question 7

Where are the adrenal glands located?

Answer 7

On top of the kidneys at the posterior wall of the abdomen

They are submerged in perineal fat

Question 8

What are the different parts of the adrenal glands and what do they secrete?

Answer 8

Adrenal cortex (outer) - aldosterone and cortisol
Adrenal medulla (inner) - adrenalin and noradrenalin

Question 9

Where does the thyroid gland lie?

Answer 9

Lies at the level of C5-T1 over the cricoid cartilage

Anterior to the trachea and oesophagus

Question 10

Where are the parathyroid glands located and how many are there?

What is their function?

Answer 10

These are just posterior to the thyroid glands
Generally have four thyroid glands but can have more

Parathyroid glands secrete the parathyroid hormone (PTH) which acts to secrete and increase the levels of blood calcium

Question 11

What are the two major functions of the pancreas?

Answer 11

Exocrine functions - release of digestive enzymes

Endocrine functions - synthesis and release of insulin and glucose

Question 12

What is the blood supply to the pancreas?

Answer 12

From the coeliac trunk (splenic artery - main branch is the transverse pancreatic branch) and the SMA - inferior pancreatoduodenal artery

Question 13

What is the vascular connection between the hypothalamus and the anterior pituitary gland?

Answer 13

Superior hypophyseal artery from hypothalamus to infundibulum - blood can travel between the two

Question 14

What is the superior hypophyseal artery a branch of?

Answer 14

Internal carotid artery

Question 15

Where does blood from the anterior pituitary gland drain to?

Answer 15

Drains to the hypopyseal portal vein

Question 16

What is the vascular connection between the anterior pituitary gland and the posterior pituitary gland?

Answer 16

Secondary capillary plexus

Question 17

What fibres synapse at the adrenal medulla?

Answer 17

Preganglionic sympathetic fibres

Question 18

What are the three arteries to the adrenal gland and where do these branch from?

Answer 18

Superior suprarenal artery - from the inferior phrenic artery
Middle suprarenal artery - from the abdominal aorta
Inferior suprarenal artery - from the renal artery

Question 19

Where do the suprarenal veins drain to?

Answer 19

Left - left renal vein

Right - IVC

Question 20

What are the lobes of the thyroid gland?

Answer 20

Left and right lobe - some people will also have a pyramidal lobe inbetween the left and right lobes

Question 21

What is the blood supply to the thyroid gland?

Answer 21

Superior thyroid artery and inferior thyroid artery

Question 22

Where does the inferior thyroid artery branch from?

Answer 22

Subclavian artery - thyrocervical trunk

Question 23

Where does blood from the thyroid gland drain to?

Answer 23

Superior, middle and inferior thyroid veins

Question 24

Where do the superior, middle and inferior thyroid veins drain to?

Answer 24

Superior and middle - internal jugular vein

Inferior - brachiocephalic

Question 25

Which nerve runs anterior to the thyroid gland?

Answer 25

Recurrent laryngeal nerve

Question 26

Where does the head of the pancreas sit?

Answer 26

In the curve of the duodenum

Question 27

Where does the tail of the pancreas extend to?

Answer 27

Extends to the spleen

Question 28

What is the most common cause of acute pancreatitis?

Answer 28

Gallstones in the sphincter of Oddi causing a build up of bile - results in acute inflammation - digestion of the pancreas

Question 29

What is a common behavioural cause of acute pancreatitis?

Answer 29

Alcoholism