Endocrine Histology

Question 1

The Neurohypophysis is the ________ lobe of the pituitary.

Answer 1

-Posterior

Question 2

The Adenohypophysis is the _________ lobe of the pituitary.

Answer 2

-Anterior

Question 3

What are the two Acidophils (eosinophils) of the Adenohypophysis and what do they secrete?

Answer 3

• Somatotropic Cell = GH

- Mammotropic Cell = Prolactin

Question 4

What are the three Basophils of the Adenohypophysis and what do they secrete?

Answer 4

• Thyrotropic Cell = TSH
• Corticotropic Cell = ACTH
• Gonadotropic Cell = FSH & LH

Question 5

What is the pars tuberalis and what kind of cells are located there?

Answer 5

• collar of cells around the infundibular stem
• part of the adenohypophysis

-Contains gonadotropic cells (basophilic)

Question 6

Where are ADH and oxytocin synthesized? Where are they released?

Answer 6

• Neurons of the supraoptic and paraventricular nuclei in the hypothalamus
• released in pars nervosa (posterior pituitary)

Question 7

Where is the pars nervosa located?

Answer 7

-posterior pituitary

Question 8

What are the three Pars of the adenohypophysis?

Answer 8

• Pars distalis (75%)
• Pars Intermedia
• Pars tuberalis

Question 9

Neurons of what nuclei influence hormone release in the anterior pituitary?

Answer 9

-dorsal & ventral medial and infundibulary nuclei

Question 10

Neurons of what nuclei release hormones in the posterior pituitary?

Answer 10

Supraoptic and paraventricular nuclei

Question 11

What is a Herring Body?

Answer 11

• Secretory material in the neurohypophysis

- Storage of secretory elements

Question 12

What are Pituicytes?

Answer 12

-basically glial cells for the posterior pituitary

Question 13

What are the principal cell types of the Thyroid gland?

Answer 13

• Follicular Cells

- Parafollicular cells (C-cells)

Question 14

What is found on the inside of a thyroid follicle?

Answer 14

-colloid

Question 15

Where is thyroglobulin stored?

Answer 15

-lumen colloid of thyroid gland

Question 16

What happens to thyroglobulin?

Answer 16

-it is iodinated in the lumen of the follicle, forming T3 and T4. This is then secreted basally into a capillary

Question 17

What does T3 do?

Answer 17

• increases basal metabolic rate
• stimulates mitochondiral respiration
• increases number of mitochondria and cristae

Question 18

What is the embryological origin of C-cells in the thyroid?

Answer 18

Neural crest

Question 19

What do C-cells do?

Answer 19

-produce and secrete Calcitonin

Question 20

What are the principal cells of the Parathyroid Glands?

Answer 20

• Chief Cells

- Oxyphil cells

Question 21

What are the parathyroid glands important for?

Answer 21

-calcium homeostasis

Question 22

What do chief cells of the Parathyroid do?

Answer 22

-secrete PTH in response to low Ca levels

Question 23

What do Oxyphil Cells do?

Answer 23

• Unknown function
• Have lots of mitochondria (eosinophilic)
• may be transitional chief cells

Question 24

What is a result of hyperparathyroidism?

Answer 24

• multiple sites of bone deposition (bone cysts)

- Kidney stones

Question 25

What is a result of Hypoparathyroidism?

Answer 25

- low serum calcium | - Muscle spasms and convulsions

Question 26

What does the Pineal Gland do?

Answer 26

- regulates circadian rhythm | - secretes Melatonin in relation to light/dark cycles

Question 27

What are the main cells of the Pineal Gland?

Answer 27

-Pinealocytes

Question 28

What is the embryological origin of the cortex and medulla of the adrenal glands?

Answer 28

Cortex: Mesoderm Medulla: Neural Crest

Question 29

What gland regulates the Adrenal Cortex?

Answer 29

-pituitary

Question 30

What is secreted by the Adrenal Cortex?

Answer 30

-steroid hormones

Question 31

What is produced and secreted by the Adrenal Medulla?

Answer 31

-Catecholamines

Question 32

What are the three zones of the Adrenal Cortex, in order of outer to inner?

Answer 32

- Zona Glomerulosa - Zona Fasciculata - Zona Reticularis

Question 33

What class of hormones is produced in the Zona Glomerulosa?

Answer 33

-Mineralcorticoids

Question 34

What class of hormones is produced in the Zona Fasciculata?

Answer 34

-Glucocorticoids

Question 35

What class of hormones is produced in the Zona Reticularis?

Answer 35

-Androgens

Question 36

What is the histological appearance of Adrenal Cortex cells?

Answer 36

foamy

Question 37

(T/F) The adrenal cortical and medullary arteries are separate.

Answer 37

T

Question 38

What is the primary Mineralcorticoid?

Answer 38

-aldosterone

Question 39

What is the primary glucocorticoid?

Answer 39

-Cortisol

Question 40

What is the primary Catecholamine released by the Adrenal Medulla?

Answer 40

Epinephrine (80%)

Question 41

What is the functional cell of the Adrenal Medulla?

Answer 41

-Chromaffin Cells

Question 42

What is PNMT (Phenylethnolamine N-methyltransferase)?

Answer 42

-enzyme that converts Norepinephrine to Ephinephrine in the Adrenal Medulla

Question 43

What do Delta cells of the Pancreas release?

Answer 43

- Gastrin - Somatostatin - VIP

Question 44

What does Somatostatin do?

Answer 44

-inhibits insulin and Glucagon

Question 45

What do Follicular cells of the Thyroid do?

Answer 45

- produce Thyroglobulin and secrete apically into lumen - Take up iodide, oxidise to iodine, and secrete apically to lumen - Take up T4/3, secrete basally

Question 46

What causes Goiter?

Answer 46

- thyroglobulin is produced, secreted to lumen, but never iodinated - builds up, swelling the thyroid gland

Question 47

What is Myxedema?

Answer 47

-adult hypothyroidism

Question 48

What is Graves Disease?

Answer 48

-Hyperthyroidism