Pituitary Gland

Question 1

What are the endocrine glands that are influenced by the pituitary gland?

Answer 1

Thyroid gland
adrenal gland
testis
ovary

Question 2

Other glands influenced by the pituitary

Answer 2

mammary gland
skeleton, muscle, and fat tissues
uterus
kidney

Question 3

Embryological derivative of neurohypothesis

Answer 3

brain (neuroectoderm)

Question 4

Embryological derivative of adenohypothesis

Answer 4

Epithelium Oral ectoderm (rathke’s pouch)

Question 5

Components of the posterior lobe

Answer 5

pars intermedia

pars nervosa

Question 6

components of anterior lobe

Answer 6

pars distalis

Question 7

What are the two parts of the infundibulum

Answer 7

infundibulum stalk

median eminence

Question 8

What part of the pituitary sits at the front of the organ

Answer 8

pars distalis

Question 9

Location of pars tuberalis

Answer 9

sits over the infundibular stalk

Question 10

(adeno-/Neurohypothesis) stains better

Answer 10

adenohypothesis

Question 11

(adeno-/Neurohypothesis) is the secretary portion of the organ

Answer 11

adenohypothesis

Question 12

2 different embryological origins of the organs explains the presence of what structure

Answer 12

rathke’s pouch

Question 13

What attaches the pituitary gland to the brain

Answer 13

median eminence

Question 14

what part of the brain is the pituitary gland attached to

Answer 14

hypothalymus

Question 15

Which part(s) of the pituitary gland contain PAS positive cells

Answer 15

Pars intermedia and a few cells in the pars distalis

Question 16

What are the 3 considerations to have in mind when you look at a section of the pituitary

Answer 16

• Orientation of the organ when cut
• level at which the organ was cut
• Plane of sectioning (horizontal, saggital, etc)

Question 17

What artery supplies the adenohypothesis

Answer 17

superior hypophyseal a.

Question 18

What artery supplies the pars nervosa

Answer 18

inferior hypophyseal a.

Question 19

What vein drains both the aden- and neruorhypothesis

Answer 19

inferior hypophyseal v.

Question 20

What captures the releasing factors after they are made by the hypothalymus

Answer 20

capillary beds in the median eminence

Question 21

How do the releasing factors get from the capillary bed in the median eminence to the sinusoids in the pars distalis

Answer 21

long and short portal veins

Question 22

Releasing factors (promote/inhibit) hormone secretion by the pars distalis

Answer 22

both

Question 23

What two hormones are released into the blood circulation by the pars nervosa

Answer 23

oxytocin and vasopressin (ADH)

Question 24

What artery forms the sinusoids in the pars nervosa

Answer 24

inferior hypophyseal a

Question 25

Where are oxytocin and vasopressin delivered from in the pars nervosa

Answer 25

brain

Question 26

How do oxytocin and vasopressin get into circulation

Answer 26

inferior hypophyseal v.

Question 27

Know the HH portal system and HH tract

Answer 27

ok

Question 28

What are the names of the 2 nuclei involved in the HH tract **(Double check)

Answer 28

periventricular nucleus and supraoptic nucleus

Question 29

What are the names of the 2 nuclei involved in the HH portal system **(Double check)

Answer 29

preoptic area and arcuate nucleus

Question 30

What structure separates groups of cells in the pars distalis

Answer 30

sinusoidal capillaries

Question 31

Two distinct characteristics of sinusoidal capillaries

Answer 31

Lined by single layer of epithelium and are larger than true capillaries

Question 32

The epithelium in sinusoidal capillaries found in the pars distills is...

Answer 32

fenestrated with diaphragms

Question 33

Why is the epithelium in the sinusoidal capillaries fenestrated with diaphragms

Answer 33

to facilitate the uptake of pituitary hormone and transport it through the blood

Question 34

3 types of cells in the pars distalis

Answer 34

chromophobs, basophils, and acidophils

Question 35

Neumonic for hormones secreted by the pituitary gland

Answer 35

``` FLAT PIG F= FSH L=LH A=ACTH T=TSH P=Prolactin I=Ignore G=Growth hormone ```

Question 36

What hormones are secreted by the acidophil cells

Answer 36

GH and Prolactin

Question 37

What explains the different staining patterns we see between the acidophils, basophils, and chromophobs

Answer 37

contents in their secretion granules

Question 38

Do chromophob contain secretion granules?

Answer 38

no- thats why their cytoplasm is unstained

Question 39

Where are basophils commonly found in the pituitary

Answer 39

centrally

Question 40

Where are acidophils commonly found in the pituitary

Answer 40

laterally

Question 41

Where are chromophobs commonly found in the pituitary

Answer 41

in the pars intermedia

Question 42

What cell (acidophil/basophil/chromophob) stains with PAS in addition to H&E

Answer 42

basophil

Question 43

What is the name of the basophil cell that secretes TSH

Answer 43

Thyrotroph (makes sense because TSH=Thyroid stimulating hormone)

Question 44

What is the name of the basophil that releases ACTH

Answer 44

Corticotroph

Question 45

What is the name of the acidophil that releases growth hormone

Answer 45

Somatotroph

Question 46

What is the only cell that releases two hormones

Answer 46

gonadotroph

Question 47

What is the basophil that releases LH and FSH

Answer 47

Gonadotroph

Question 48

What is the acidophil that releases prolactin

Answer 48

mamotroph (makes sense because mammals lactate)

Question 49

List two examples of hybrid cells

Answer 49

mammosomatotroph and corticogonadotroph

Question 50

Hormones secreted by the mammosomatotroph

Answer 50

Prolactin and GH

Question 51

Hormones secreted by the corticognadotroph

Answer 51

FSH, LH, and ACTH

Question 52

List the 5 acidophil and basophil cells in order of granule size (largest to smallest)

Answer 52

mammotroph, sommatotroph, gonadotroph, corticotroph, and thyrotroph

Question 53

Distribution of the thyrotrophs

Answer 53

Central and in the front of the pars distalis (Anterior and medial)

Question 54

Distribution of the corticotroph

Answer 54

center behind the thyrotroph in the pars distills, pars intermedia, and border of pars nervosa

Question 55

Distribution of the gonadotroph

Answer 55

all throughout the pars distalis

Question 56

Distribution of the sommatotroph and mammotroph

Answer 56

Scattered along the lateral wings of the pars distalis

Question 57

The principle cells of the adenohypothesis are blank cells

Answer 57

secretory cells

Question 58

The principle cell in the neurohypothesis are blank type of cells

Answer 58

support cells (pituicytes)

Question 59

The neurohypothesis stains (well/poorly)

Answer 59

poorly

Question 60

What nuclei gives rises to oxytocin

Answer 60

periventricular nuceli

Question 61

which nuclei gives rise to vasopressin (ADH)

Answer 61

supraoptic nuclei

Question 62

Pituocytes are located between blank and have blank protruding from their cell bodies

Answer 62

unmyelinated axon nerve fibers, cytoplasmic processes

Question 63

Morphology of herring bodies

Answer 63

large, round acidophilic swellings of axons

Question 64

Function of herring bodies

Answer 64

Sites of hormone accumulation (storage site for hormones

Question 65

Endothelium in sinusoidal capillaries in the neurohypothesis is

Answer 65

fenestrated with diaphragms

Question 66

What are the types of vessicles present in the nerve fibers of the neurohpothesis

Answer 66

endocytotic vessicles

Question 67

What are the cellular contents present in the cells of the neurohypothesis

Answer 67

mitochondria, endocytotic vessicles, SER, microtubules, and microfilaments

Question 68

What contents are released from the nerve terminals in the neurohypothesis

Answer 68

Oxytocin and vasopressin

Question 69

Visible morphologies of the pituicyte (2)

Answer 69

nuclei and cytoplasmic processes

Question 70

Compare the histology of an endocrine glands verses an exocrine

Answer 70

Exocrine: Organized into small round group of cells called an acini or elongated tubules. The secretions are carried via a duct. Endocrine: Secretions are released into a capillary bed and carried by blood to target organ. Cells organized into round masses (islets) infiltrated with extensive capillary bed.

Question 71

Why does the paucity stain poorly

Answer 71

absence of secretion granules (neurohypothesis is not the secretory part of the organ)

Question 72

Two reasons why the neurohypothesis is poorly stained relative to the adenohyopthesis

Answer 72

- presence of unmyelinated nerve fibers | - Pituicytes lack secretion granules

Question 73

The hypothalamohypophyseal portal system (HH portal system) is analogous to

Answer 73

the portal system in the liver (vein --> capillary bed --> vein)

Question 74

Sinusoids the the pars tubercles represent the distal ends of...

Answer 74

hypophyseal veins

Question 75

The infundibular stalk and pars tubercles are connected by

Answer 75

short sinusoids

Question 76

Why are sinusoidal capillaries of the pituitary gland refered to as false capillaries

Answer 76

Because they are larger than true capillaries (1 RBC in diameter)

Question 77

How many hormones are secreted by the pituitary gland

Answer 77

6

Question 78

Reasons why the chromophob cytoplasm does not stain

Answer 78

- Lacks organelles (inactive cell) | - Doesn't store hormone (secretes after synthesis)

Question 79

Does the chromophob nucleus stain?

Answer 79

Yes- very prominent

Question 80

What makes the arrangement of cells in the pituitary gland different from an acinus in exocrine glands

Answer 80

The cells are not oriented towards an acinar lumen, they are arranged such that they are in contact with a sinusoidal capillary

Question 81

Pituicytes are similar to blank cell

Answer 81

astrocyte

Question 82

The only part of the pitufcyte that stains is the...

Answer 82

nucleus

Question 83

What type of junctions form between pitufcyte processes

Answer 83

gap junctions and desmosomes

Question 84

Another role for the pituicyte other than support cells for the unmyelinated nerve fibers

Answer 84

Controls the movement of hormone (processes from pituicytes narrow the extracellular space to restrict hormone movement)

Question 85

describe the blood-brain barrier

Answer 85

continuous capillaries with hight auctions- prevents the passage of materials in the blood to the brain

Question 86

Since the neurohypothesis is derived from the brain, does the pars nervosa have the bold-brain barrier?

Answer 86

No the sinusoidal capillaries in the pars nervosa are fenestrated with diaphragms

Question 87

Describe the movement of vasopressin/oxytocin

Answer 87

- Hormone is released from herring bodies - Hormone is released into the extracellular gap between the pitufcyte processes (may control the flow of hormone) - Hormone enters blood through fenestrations in the endothelium of the capillaries - Excess hormone in the extracellular space is removed by pituicytes by phagocytosis of the hormone