Downing: Pituitary Histology

Question 1

What are the three components of the adenohypophysis?

Answer 1

1. Pars distalis
2. pars intermedia
3. Pars tuberalis

Question 2

What forms 75% of the hypophysis?

Answer 2

Pars distalis

Question 3

What are the two categories of cell types seen in the pars distalis?

Answer 3

1. Chromophobes (null cells)(50%)

2. Chromophils (50%)

Question 4

What cells in the par distalis appear in CLUSTERS, with nuclei surrounded by light cytoplasm that may be degranulated by acidophils and basophils?

Answer 4

Chromophobes

Question 5

What are the two types of cells that form chromophils?

Answer 5

Acidophils (40%) and Basophils (10%)

slightly larger than acidophils

Question 6

What are the two types of acidophilic secretory vesicles?

Answer 6

Somatotrophs

Mammotrophs

Question 7

Somatotrophs (acidophile)

Answer 7

GH

somatotropin/STH

Question 8

Mammotrophs (acidophile)

Answer 8

PRL

Question 9

What cell number increases during pregnancy and lactation?

Answer 9

Mammotrophs

Question 10

What are the three types of basophilic secretory vessicles?

Answer 10

thyrotrophs
gonadotrophs
corticotrophs

Question 11

What secretes TSH?

Answer 11

Thyrotrophs

Question 12

What secretes FSH and LH?

Answer 12

Gonadotrophs

Question 13

What secretes ACTH and MSH?

Answer 13

Corticotrophs

Question 14

What part of the adenohypophysis produces MSH?

Answer 14

Pars intermedia (weakly basophilic)

Question 15

Where are Rathke’s cysts located and what do they contain?

Answer 15

Pars intermedia

Remnants of Rathke’s pouch= follicles lined by cuboidal epithelium and filled w/ colloid

Question 16

Where do the superior hypophyseal arteries terminate to from the primary plexus of the portal system?

Answer 16

Pars tuberalis

Question 17

Cells in the pars tuberalis contain…

Answer 17

FSH

LH

Question 18

What releases GH? What inhibits GH?

Answer 18

+ SRH

- Somatostatin

Question 19

What hormone increases metabolic rate and stimulates liver cells to release STOMATOMEDINS leading to an increased proliferation of CARTILAGE and growth in LONG BONES?

Answer 19

GH

Question 20

What releases prolactin? What inhibits prolactin?

Answer 20

+ PRH

- PIF

Question 21

What hormones promotes the development of MAMMARY GLANDS during pregnancy and stimulates MILK PRODUCTION after parturition?

Answer 21

Prolactin (stimulated by suckling)

Question 22

What releases ACTH?

Answer 22

CRH

Question 23

What stimulates the synthesis and release of hormones from the suprarenal cortex? What are these hormones?

Answer 23

CRH

Cortisol
corticosterone

Question 24

What releases FSH? What inhibits FSH?

Answer 24

+ GnRH

- Inhibin (Males)

Question 25

What stimulates secondary ovarian follicle growth and estrogen secretion as well as SERTOLI cells in the seminiferous tubules to produce ABP?

Answer 25

FSH

Question 26

What releases LH and ICSH?

Answer 26

+ GnRH

Question 27

What hormone assists FSH in promoting OVULATION, the formation of the COPRUS LUTEM, and secretion of PROGESTERONE AND ESTROGEN (F)? Stimulates LEYDIG cells to secrete/release testosterone> negative feedback to hypothalamus to inhibit GnRH in men?

Answer 27

LH | ICSH

Question 28

What releases and inhibits RSH?

Answer 28

+ TRH | - negative feedback suppresses via CNS

Question 29

What stimulates the release of thyroid hormone and increases the metabolic rate?

Answer 29

TSH

Question 30

What hormones are found i the pars distalis?

Answer 30

``` GH PRL ACTH FSH LH/ICSH TSH ```

Question 31

What hormones are found in the pars nervosa?

Answer 31

oxytocin | vasopressin

Question 32

What does oxytocin do?

Answer 32

Smth musc contractions of UTERUS during ORGASM Contractions of uterus at parturition Suckling> oxytocin release> contraction of myoepithelial cells in mammmary glands/milk ejection

Question 33

What hormone increases water absorption by the kidneys and is regulated by osmotic pressure?

Answer 33

vasopressin

Question 34

What hormone can restore normal BP after severe hemorrhage?

Answer 34

Vasopressin

Question 35

What are the two embryological derviations of the pituitary gland?

Answer 35

Oral ectoderm | Neural ectoderm

Question 36

The adenohypophysis is derived from?

Answer 36

oral ectoderm

Question 37

the neuohypophysis is derived from?

Answer 37

neural ectoderm

Question 38

The pars tuberalis, pars distalis and the pars intermedia are divisions of the ___________and are therefore derivations of _______.

Answer 38

Adenohypophysis | Oral ectoterm

Question 39

The pars nervosa and infundibulum are divisions of the __________ and are therefore derived from __________.

Answer 39

Neurohypophysis | Neural ectoderm

Question 40

What forms the neural lobe?

Answer 40

pars nervosa

Question 41

What forms the neural stalk?

Answer 41

infundibulum

Question 42

What forms the infundibular stem and the median eminence of the tuber cinereum?

Answer 42

Infundibulum

Question 43

What is the hypophyseal portal system?

Answer 43

Blood vessels that connects the HYPOTHALAMUS with the ANTERIOR PITUITARY

Question 44

Where is the hypothalamu hypophyseal tract located?

Answer 44

Passes through the INFUNDIBULAR STALK and ends in the PARS NERVOSA

Question 45

What hormone is most abundant in cell bodies of the PARAVENTRICULAR NUCLEI?

Answer 45

Oxytocin

Question 46

What hormone is most abundant in cell bodies of SUPRAOPTIC NUCLEI?

Answer 46

ADH/vasopressin

Question 47

What stimulates the milk ejection reflex?

Answer 47

suckling> secretion oxytocin> contraction myoepithelial cells surrounding alveoli in mammary glands

Question 48

What is the fxn of ADH?

Answer 48

Increases water reabsorption in DCT> | hypertonic urine

Question 49

What stimulates ADH secretion?

Answer 49

increase in plasma osmolarity | decrease in blood volume

Question 50

What causes diabetes insipidus?

Answer 50

Lack of ADH | makes you pee a lot and drink a lot