Histology of Endocrine Organs

Question 1

What is the infundibulum?

Answer 1

Pituitary Stalk

Question 2

What are Tropic Hormones (and list them)

Answer 2

Hormones from the hypothalamus

TRH
CRH
Somatostatin
GHRH
GnRH
Dopamine

Question 3

What is the Pars Nervosa?

Answer 3

Body of the Posterior Pituitary Gland

Question 4

What is the Pars Intermedia?

Answer 4

The section between the bodies of the anterior and posterior pituitary gland

Question 5

What is the Pars Distalis?

Answer 5

The body of the anterior pituitary gland

Question 6

What is the Pars Tuberalis?

Answer 6

Part of the anterior pituitary gland that makes up the Infundibulum (pituitary stalk)

Question 7

How do you tell the difference between the Pars Distalis and the Pars Nervosa?

Answer 7

Pars distalis is is darker, more heavily stained than the Pars Nervosa

Question 8

What is the embryological origin of the Pars Distalis?

Answer 8

Rathke’s Pouch

Question 9

What is the embryolgical origin of Pars Nervosa and the Pituitary stalk?

Answer 9

Infundibulum

Question 10

What are somatotropic cells?

Answer 10

Cells of the anterior pituitary gland that secrete GH

Question 11

What are Thyrotropic cells?

Answer 11

cells of the anterior pituitary gland that secrete TSH

Question 12

What are corticotropic cells?

Answer 12

Cells of the anterior pituitary gland that secrete ACTH and MSH

Question 13

What are gonadotropic cells?

Answer 13

Cells of the anterior pituitary gland that secrete LH ans FSH

Question 14

What are Mammotropic cells?

Answer 14

Cells of the anterior pituitary gland that secrete Prolactin

Question 15

What are acidophils?

Answer 15

Acidphils are cells in the anterior pituitary

They are the Somatotrophic cells and the Mammotropic cells

They stain pink

Question 16

What are the basophils?

Answer 16

Basophils are cells in the anterior pituitary

They are the Gonadotropic cells, corticotropic cells, and the Thyrotropic cells

They stain dark pink/purple

Question 17

What are chromophobes?

Answer 17

Cells in the anterior pituitary

Have no known function

Called chromophobes because their cytoplasm does not stain

They appear like fried eggs with clear, stainless cytoplasm, but a dark nucleus in the cener

Question 18

What are the hormones of the anterior pituitary gland?

Answer 18

TP - FLAG

TSH
Prolactin
FSH
LH
ACTH
GH

Question 19

What structures will you find in the Pars Nervosa, but not in the Pars Distalis?

Answer 19

Herring Bodies

These are expanded axonal nerve terminals storing ADH and oxytocin

Question 20

What is the role of the Pineal Gland?

Answer 20

Growth, development, and circadian rhythms

Synthtesizes serotonin and melatonin

Question 21

What structure should you look for when trying to identify a slide containing Pineal Gland tissue?

Answer 21

Brain Sand

Calcium Phosphate crystals which stain darkly

Question 22

What structure should you look for when trying to identify a slide containing Thyroid Gland tissue?

Answer 22

Follicles containing a pinkly stained fluid called Colloid

Question 23

Which endocrine gland is the only one that stores hormones outside of the cells?

Answer 23

Thyroid gland

Thyroid hormone stored in colloid fluid of thyroid follicles

Question 24

What is Grave’s Disease?

Answer 24

Grave’s Disease occurs when abnormal antibodies are developed that act as TSH analogs, resulting in over-secretion of T3 and T4

Symptoms: Sweating, elevated metabolism, rapid heart rate, weight loss, eyeballs may protrude

Treated by thyroidectomy or anti-thyroid medication

4-8x more common in women

Question 25

What is hypothyroidism?

Answer 25

Insufficient T3/T4 secretion from thyroid gland Often caused by auto-immune disorder that attacks follicle cells of the thyroid Symtpoms: Low metabolic rate, weight gain, chilliness, edems, lethargy (lack of energy/enthusiasm) Treated with synthetic T3/T4 administration

Question 26

What are goiters?

Answer 26

Goiters are enlarged thyroid glands most commonly caused by iodine deficiency Thyroglobulin is produced by is not iodinized to make Thyroid Hormone Thyroglobulin accumulates in the gland, causing it to enlarge

Question 27

What are the two cell types found in the parathyroid gland and what do they do?

Answer 27

Chief Cells - secrete PTH when serum calcium levels are low Oxyphil Cells - Unknown function

Question 28

What are the 3 tissue layers of the adrenal cortex from most superficial to deep?

Answer 28

Think GFR: Zona Glomerulosa Zona Fasciculata Zona Reticularis

Question 29

What tissue layer(s) of the adrenal cortex is Aldosterone secreted from?

Answer 29

Zona Glomerulosa - Secretes mineralocorticoids

Question 30

What tissue layer(s) of the adrenal cortex are adrenal androgens secreted from?

Answer 30

Zona Reticularis - influences secondary sexual characteristics

Question 31

What tissue layer(s) of the adrenal cortex is Cortisol secreted from?

Answer 31

Mostly secreted from the Zona Fasciculata - Secretes all glucocorticoids, including Cortisol. Also is secreted (less so) from the Zona Reticularis

Question 32

What part of the adrenal gland are epinephrine and norepinephrine secreted from?

Answer 32

Adrenal Medulla

Question 33

What are the cells found in the adrenal medulla what do they do?

Answer 33

Adrenal medulla contains chromaffin cells which secrete epinephrine and norepinephrine in response to sympathetic innervation from presynaptic neurons

Question 34

What is Addison's Disease?

Answer 34

Think JFK Addison's disease is when there is hyposecretion of glucocorticoids and mineralocorticoids Adrenal gland does not secrete enough corticoid hormones, particularly cortisol and aldosterone. Caused by autoimmune disease Symptoms include low blood sodium/glucose levels, dehydration, low blood pressure, fatigue, loss of appetite, darkening of skin/gums/inside of cheek

Question 35

Why do people with Addison's develop darker skin tone?

Answer 35

When cortisol levels are decreased, CRH secretion increases, causing an increase in ACTH secretion ACTH is synthesized from POMC, which is also the molecule responsible for the synthesis of MSH. ACTH secretion stays increased due to no responsive secretion of Cortisol from the adrenal cortex (zona fasciculata) resulting in excessive production of MSH and alpha-Melanin, causing skin to get darker

Question 36

What is Cushing's Syndrome?

Answer 36

Cushing's syndrome is when you have hypersecretion of glucocorticoids Excessive amount of cortisol secretion from an Adrenal adenoma Symptoms: Fat redistribution (buffalo hump on back; moon face), high glucose levels, weight gain, sweating, thinning skin, muscle weakness, lethargy, depression of immune and inflammatory responses.

Question 37

What is Cushing's Disease?

Answer 37

Cushing's disease is when you have hypersecretion of glucocorticoids Excessive cortisol secretion as a result of hypersecretion of ACTH from a pituitary adenoma Symptoms: Fat redistribution (buffalo hump on back; moon face), high glucose levels, weight gain, sweating, thinning skin, muscle weakness, lethargy, depression of immune and inflammatory responses.

Question 38

What are the endocrine cells in the pancreas, where are they found, and what do they do?

Answer 38

Endocrine cells of the pancreas are found in the Islets of Langerhans Alpha Cells - Secrete glucagon Beta Cells - Secrete Insulin Delta Cells - Secrete Somatostatin F-Cells - Pancreatic Polypeptide

Question 39

What are the two vascular systems found in the pancreas and describe their routes

Answer 39

Acinar Vascular System supplies the pancreatic acini cells, avoiding the Islets of Langerhans The Insuloacinar Portal System supplies the Islets of Langerhans first, then supplies a portal system of vessels to the pancreatic acinar cells.