L71: Posterior Pituitary & Hypothalamic-Pit-Liver (HPL) axis Flashcards Preview

FHB - Endocrinology (by Richie) > L71: Posterior Pituitary & Hypothalamic-Pit-Liver (HPL) axis > Flashcards

Flashcards in L71: Posterior Pituitary & Hypothalamic-Pit-Liver (HPL) axis Deck (32)
1

What negatively regulates GH?

IGF-1

2

GH stimulates what in the liver?

IGF-1

3

Caveat: GH stimulates IGF1 in the liver, in an ______ dependent manner

Insulin

4

In what organs does IGF-1 mimic insulin?

Muscle, but not liver and adipose!

5

Which of the following released from hypothalamus in pulsatile manner?
A. GnRH
B. GHRH
C. GH
D. GnRH and GHRH

D. GnRH and GHRH

6

Where are all the places somatostatin is made?

SS28 - D cells in stomach/duodenum

SS14 - PVN of hypothalamus and pancreatic delta cells

7

SS14 and SS28 have identical

amino termini

8

Why does prolactinoma produce reproductive dysfunction?

Too much prolactin release negatively feeds back on hypothalamic GnRH release

9

Sheehan's syndrome

prolactin deficiency due to partial pituitary destruction (shock/blood loss)

10

PVN has 2 cells types

Parvicellular and magnocellular

11

Cell bodies making AVP are located in

PVN and SON

12

AVP from parvocellular PVN regulate

mood (anxiety)/stress

13

AVP from magnocellular SON and PVN regulate

fluid balance

14

What is neurophysin?

a carrier protein located in the pro hormone for both AVP and OXY

15

Along with OXY or AVP, what else is in the vesicle?

neurophysin I for OXY
neurophysin II for AVP

16

What water transporter is on the apical membrane of distal tubule cell?
A. AQP2
B. AQP 3
C. AQP 4
D. AQP 3 and 4

A. AQP2

note that AQP3 and 4 are on the basolateral membrane!

17

AVP defect in what disease?

Diabetes insipidus NOT MELLITUS

18

OXY is released by _______ neurons located in the ____.

Magnocellular, PVN

19

Induces skeletal muscle contractions at breast and uterus

OXY. Note: these are both positive control loops.

20

What's pitocin?

synthetic oxytocin used to induce labor. Sometimes physicians use this when they want to be home on time for dinner. Tsk tsk tsk.

21

OXY binds what kind of receptor, to have what effect?

GPCR, increases intracellular Ca++

22

GH is produced at what hypothalamus nucleus?

TRICK QUESTION. GHRH not GH is released at hypothalamus (Arcuate nucleus).

23

What is in the GHRH pro hormone?

GHRH + GCTP (c-terminal peptide)

24

What inhibits GHRH pulse frequency at hypothalamus, and GH and TSH release in pituitary?

SS from PeVN

25

Bonus detail: what are Furin, PC1, and PC2?

endopeptidases that process somatostatin SS28 and SS14.

26

Bonus detail: which SS predominates in brain?

SS14

27

Bonus detail: which SS predominates in intestines?

SS28

28

What is the primary anabolic goal of GH?

conserve protein

29

Structurally, GH is in the same family of

prolactin

30

Downstream GH target organ effects mediated through

IGF-1 (somatomedin)

31

What's somatomedin

IGF-1

32

T/F: GHRH is pulsatile but not GH

F: both are