Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

FHB IV- Endocrinology > Endocrinology 3 > Flashcards

Endocrinology 3 Flashcards

1
Q

Describe the anatomical organization of the hypothalamus and the major hypothalamic nuclei associated with each hypothalamic-releasing hormone.

A

Slide 7, 10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

On Slide 6, label tags 1-5.

A
  1. Cerebral peduncle
  2. Mammillary bodies
  3. Hypothalamus
  4. Optic Nerve
  5. Olfactory Tract
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the discrete nuclei into which the hypothalamus is divided.

A 
PVN = Paraventricular Nucleus
POA = Preoptic Nucleus
ARC = Arcuate Nucleus 
SCN = Suprachiasmatic Nucleus
SON = Supraoptic Nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the medial eminence? What is its significance?

A

ME = Medial Eminence
Floor of hypothalamus
Convergence point for axons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the hypothalamic functions and where they are localized.

A 
Sleep (SCN)
Feeding behavior/satiety (ARC)
Thirst (PVN)
Reproduction (POA)
Circadian rhythms (SCN)
Mood/emotion/stress (PVN/ARC)
Body temperature (POA)
Blood pressure (PVN)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where are the following localized?

Sleep
Feeding behavior/satiety 
Thirst
Reproduction 
Circadian rhythms 
Mood/emotion/stress
Body temperature 
Blood pressure
A 
Sleep (SCN)
Feeding behavior/satiety (ARC)
Thirst (PVN)
Reproduction (POA)
Circadian rhythms (SCN)
Mood/emotion/stress (PVN/ARC)
Body temperature (POA)
Blood pressure (PVN)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

For the following hormone describe the brain nuclei, pituitary target, and function:

GnRH (peptide)
GnIH (inhibitor)

A

Brain nuclei - Scattered – POA has majority

Pituitary target- Gonadotropes – FSH, LH

Function - Reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

For the following hormone describe the brain nuclei, pituitary target, and function:

CRH (peptide)

A

Brain nuclei - Paraventricular (PVN) (parvocellular)

Pituitary target- Corticotrope - ACTH

Function - Glucocorticoids – pleiotropic effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

For the following hormone describe the brain nuclei, pituitary target, and function:

TRH (peptide)

A

Brain nuclei - PVN

Pituitary target- Thyrotrope - TSH

Function - Thyroid hormone – pleiotropic effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

For the following hormone describe the brain nuclei, pituitary target, and function:

GHRH (peptide)

A

Brain nuclei - Arcuate nucleus

Pituitary target- Somatotrope - GH

Function - growth and development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

For the following hormone describe the brain nuclei, pituitary target, and function:

Somatostatin
(GHRH inhibitor)

A

Brain nuclei - Periventricular (PeVN)

Pituitary target- Somatotrope

Function - Inhibits GH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

For the following hormone describe the brain nuclei, pituitary target, and function:

Dopamine (amine)

A

Brain nuclei - Arcuate nucleus

Pituitary target- Lactotrope - prolactin

Function - Milk production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which hormones have IP3/DAG/PKC as their second messengers? About how big are they?

A

TRH- 3 aa

GnRH- 10 aa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which hormones have cAMP as their second messengers?

A

CRH- 41 aa
GHRH- 44aa
GHIH (somatostatin)- 14aa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Discuss the structure, function, receptors, and intracellular signaling pathways for GnRH.

A

GnRH is peptide hormone so signal peptide here, then 10aa GnRH then GAP which is co-peptide

whole things is prepro-GnRH
then cleaved
and released
will activate its G membrane protein receptor

slide 15

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Explain the GnRH deficiency associated with Kallman Syndrome.

A

Rare genetic disease (1:8000 men/1:40,000 women)

GnRH neurons fail to enter CNS

Characterized by reproductive failure and anosmia

Heritable: X-linked = Kal1, autosomal = Kal2

17
Q

Describe GONADOTROPIN-RELEASING HORMONE (GnRH – LHRH):

Where are cell bodies?
Where is largest concentration?
Where do axons extend toward?

What type of hormone?

A

Cell bodies scattered throughout forebrain

Relatively few (approx 1500-2000) in humans (compared to 100 billion total neurons)

Largest concentration in POA

Very long axons extend towards median eminence

GnRH is a decapeptide (10 aa)

Highly conserved among vertebrates

18
Q

Diagram the vascular connections between the hypothalamus and pituitary.

A

Slide 19

superior and inferior hypophysial arteries

hypophysial vein and portal vein

19
Q

What is the hypophysial portal system?

How was it discovered?

A

Vascular connection between the hypothalamus and pituitary gland.

When pituitaries were transplanted in other locations they stopped secreting hormones.
Once re-implanted they only worked if vascular system was re-established.

Slide 18

20
Q

How is GnRH pulsatility measured?

A

measured from portal vein

21
Q

What do the following release?

Lactotroph
mammosomatroph
somatotroph
thyrotroph
gonadotroph
corticotroph
A

Lactotroph- Prolactin

mammosomatroph- prolactin and growth hormone

somatotroph- growth hormone

thyrotroph- thyrotropin

gonadotroph- LH, FSH

corticotroph- corticotropin

22
Q

Explain the importance of hypothalamic and pituitary hormone pulsatility.

A

Slide 23-26

Pulse frequency determines which gonadotropin subunit is released

23
Q

Explain the difference between the tuberoinfundibular system and the neurohypophysial tract.

A

Tuberoinfundibular System - comprises all neurons that send axonal projections to the median eminence. Hormones target the anterior pituitary through the capillary system (endocrine).

  1. Neurohypophysial Tract – comprises neurons whose axons terminate in the posterior pituitary.
24
Q

Compare and contrast the anatomical organization of the anterior and posterior pituitary gland and identify which hypothalamic hormones target each lobe.

A

POSTERIOR PITUITARY – NEUROHYPOPHYSIS
Axons from magnocellular neurons terminate in neurohypophysis (“neurohypophysial tract”).

Blood supply from inferior hypophysial artery – has its own capillary bed.

Major hormones: Arginine vasopressin (AVP) and oxytocin (OXY).
Slide 34

ANTERIOR PITUITARY – ADENOHYPOPHYSIS
Median eminence (ME) is the interface for all hypophysiotrophic hormones.

ME lies outside the blood brain barrier and forms the floor of the 3rd ventricle.

25
Q

Identify important histological features that distinguish the anterior and posterior lobes of the pituitary.

A

Anterior Pituitary
Pars distalis (90%)
Pars tuberalis
Pars intermedia

Posterior pituitary
Pars nervosa
Infundibulum (stalk)

Adenohypophysis (anterior pituitary)
-Glandular tissue: Cords of epithelial cells

Neurohypophysis (posterior pituitary)
-Neural tissue: Terminal axons and glial cells

26
Q

In pars nervosa, where do axons terminate?

A

near fenestrated capillaries

27
Q

Where are pituicytes located?

A

pars nervosa of posterior pituitary

28
Q

What are Herring bodies?

A

Herring bodies = dilations of unmyelinated axons near their terminals. Contain vesicles of either AVP or Oxytocin plus a binding protein, neurophysin.

29
Q

What is neurophysin?

A

Herring bodies = dilations of unmyelinated axons near their terminals. Contain vesicles of either AVP or Oxytocin plus a binding protein, neurophysin.

30
Q

Describe the 5 major cell types in the anterior pituitary and explain which cells are responsible for synthesizing and secreting LH/FSH, TSH, GH, ACTH, and Prolactin.

Where in the pituitary are these clustered? DRAW.

A

Acidophils – (40%) most abundant

Somatotrophs = growth hormone (GH)

Lactotrophs = prolactin (lactation)

Basophils (10%)
Corticotrophs = ACTH (stress)

Gonadotrophs = LH/FSH (reproduction)

Thyrotrophs = thyroid stimulating hormone (TSH)

Chromophobes (50%)
Paracrine actions

Slide 40

31
Q

Draw quick pathway from hypothalamus (magnocellular neuron) and hypothalamus (parvicellular neuron).

A

Slide 41

32
Q

What is important to keep in mind when taking blood samples to evaluate endocrine disease?

A

Most pituitary hormones have a circadian rhythm

Important consideration when taking blood samples to evaluate endocrine disease

Slide 42

33
Q

Which two hormones are not regulated by HP endocrine axes?

A

Arginine vasopressin (AVP) and oxytocin (OXY).

Axons from magnocellular neurons terminate in neurohypophysis (“neurohypophysial tract”).
Slide 33

(these aren’t regulated by HP endocrine axes bc ones regulated by those dump their contents into portal system)

34
Q

Describe the anterior and posterior pituitary blood supply.

A

Pituitary Blood Supply. Superior hypophysial artery gives rise to capillary plexus = “portal plexus” in anterior pituitary. Breaks into a primary capillary plexus within the median eminence. Then drains into hypophyseal portal veins and the secondary capillary plexus located in pars distalis.

Inferior hypophysial artery supplies the posterior pituitary

FHB IV- Endocrinology (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions