13. Endocrine System

Question 1

What does the pituitary do?

Answer 1

Coordinates the endocrine organs through feedback loops

Question 2

What are the 2 functional components of the pituitary?

Answer 2

Posterior and Anterior Pituitary

Question 3

What is the posterior pituitary?

Answer 3

Downward extension of hypothalamus

Question 4

What is the neural tissue of the posterior pituitary?

Answer 4

Axons and glial cells

Question 5

What does the posterior pituitary store/secrete?

Answer 5

Oxytocin and Antidiuretic hormones

Question 6

Describe the anterior pituitary.

Answer 6

• Nested epithelial cells
• Richly vascular fibrous stroma
• Several different types of epithelial cell not distinguishable on H&E

Question 7

What are the 5 anterior pituitary epithelial cell types?

Answer 7

• Somatotrophs
• Lactotrophs
• Corticotrophs
• Gonadotrophs
• Thyrotrophs

Question 8

What do somatotrophs secrete?

Answer 8

Growth hormone

Question 9

What do lactotrophs secrete?

Answer 9

Prolactin

Question 10

What do corticotrophs secrete?

Answer 10

ACTH
Alpha-MSH
Beta-lipotrophin
Beta-endorphin

Question 11

What do gonadotrophs secrete?

Answer 11

FSH and LH

Question 12

What do thyrotrophs secrete?

Answer 12

TSH

Question 13

Where are somatotrophs present?

Answer 13

Throughout the anterior pituitary gland, lateral wings of anterior pituitary

Question 14

Describe lactotrophs.

Answer 14

• Polygonal cells
• Cytoplasmic processes wrap around other cells
• Variable prolactin staining

Question 15

Describe thyrotrophs.

Answer 15

• Angular chromophobes
• Elongated cytoplasmic processes
• Variable TSH staining

Question 16

Describe gonadotrophs.

Answer 16

Scattered round/oval cells

Question 17

What do gonadotrophs stain with?

Answer 17

Alpha subunit, beta LH and beta FSH

Question 18

Describe corticotrophs.

Answer 18

• Round basophilic cells
• Median of gland
• Large cytoplasmic vacuoles

Question 19

What are the anterior pituitary supporting cells?

Answer 19

Sustentacular cells that surround normal follicles

Question 20

Describe the pineal gland.

Answer 20

Pinealocytes in rosettes
Brain sand

Question 21

What does the pineal gland secrete?

Answer 21

Melatonin

Question 22

What are the epithelial cells of the thyroid?

Answer 22

Follicular cells and colloid cells that are richly vascular

Question 23

The thyroid gland produces what?

Answer 23

Thyroxine and Calcitonin

Question 24

What sits between the follicles in the thyroid gland?

Answer 24

C-cells

Question 25

What are the 3 epithelial cell types of the parathyroid glands?

Answer 25

Chief cells, oxyphils and adipocytes

Question 26

What does the parathyroid gland secrete?

Answer 26

Parathyroid hormone (PTH)

Question 27

Describe the parathyroid chief cells.

Answer 27

- Polygonal cells - Scant cytoplasm

Question 28

What do the chief cells of the parathyroid gland do?

Answer 28

Raise serum Ca2+

Question 29

Describe parathyroid gland oxyphil cells.

Answer 29

- Large polygonal cells - Increase with age - Abundant eosinophilic cytoplasm - Finely granular - Unknown function

Question 30

What are Islets of Langerhans?

Answer 30

Balls of cells with a thin fibrous capsule mostly in the pancreatic tail

Question 31

What are the 4 epithelial cells of the endocrine pancreas?

Answer 31

- Beta cells - Alpha cells - Delta cells - PP cells

Question 32

What do B cells produce?

Answer 32

Insulin

Question 33

What do A cells produce?

Answer 33

Glucagon

Question 34

What do D cells produce?

Answer 34

Somatostatin

Question 35

What do PP cells produce?

Answer 35

Pancreatic polypeptide

Question 36

What are the 3 epithelial parts of the adrenal cortex?

Answer 36

- Zona glomerulosa - Zona fasciculata - Zona reticularis

Question 37

What does the zona glomerulosa produce?

Answer 37

Aldosterone

Question 38

Describe the zona glomerulosa.

Answer 38

- Thin, incomplete - Small cells - Vacuolated cytoplasm

Question 39

What does the zona fasiculate produce?

Answer 39

Cortisol

Question 40

Describe the zona fasiculate.

Answer 40

- Most prominent - Large polygonal cells - Almost clear cytoplasm

Question 41

What does the zona reticularis produce?

Answer 41

Androgenic steroids

Question 42

Describe the zona reticularis.

Answer 42

- Innermost cortical layer - Anastomosing columns of small polygonal cells

Question 43

What epithelial cells are in the adrenal medulla?

Answer 43

Chromaffin cells

Question 44

Describe the adrenal medulla.

Answer 44

- Centre of adrenal gland - Large polyhedral

Question 45

What is secreted from the adrenal medulla?

Answer 45

Adrenalin and noradrenalin

Question 46

What is a phaeochromocytoma?

Answer 46

Rare malignant tumour of adrenal medulla