Graphs & Histology - Highlights & Must-knows Flashcards Preview

FHB - Endocrinology (by Richie) > Graphs & Histology - Highlights & Must-knows > Flashcards

Flashcards in Graphs & Histology - Highlights & Must-knows Deck (27)
Loading flashcards...
1
Q

Kd vs. Ki graphs

A

2
Q

TSH stimulation tests…

A

3
Q

radioactive iodine uptake graphs…

A

4
Q

What’s the take home message here?

A

BIG IDEA: ligand concentration for maximal physiological response does not necessarily correlate with Kd! In other words, there is a certain threshold number of receptors that need to be bound, in order to induce a response. This is related to the idea of “potency” (that we didn’t really talk about explicitly) which refers to how much of the drug is necessary to create a response.

5
Q

What does this graph mean?

A

Inhibition constant (Ki) stuff…

6
Q

What does this graph indicate?

A

Dissociation constant (Kd) stuff…

7
Q
A

Melatonin synthesis (via N-acetyl transferase, or “SNA”) peaks at night.

8
Q

Explain primary failure here

A

Primary failure - high baseline serum TSH because the thyroid is not producing T3/4, so no negative feedback to both (1) the hypothalamus to stop secreting TRH thus promoting TSH and (2) to anterior pituitary to stop secreting TSH

9
Q

Explain secondary failure here

A

Secondary failure is at the level of the anterior pituitary, whose job is to make TSH. Thus, the baseline TSH levels will be very low - almost null. Also, the anterior pituitary will not be responsive to TRH from the hypothalamus. That’s why its a LOW and FLAT line all throughout!

10
Q

What are some observations here?

A

After ~50 years old, BOTH men and women show an INCREASE in

(1) Catecholamines
(2) Glucocorticoids
(3) IL-6

11
Q

Take home?

A

Who has the most BNP?

SKINNY OLD WOMEN WITH HEART FAILURE.

Note: Normal levels of BNP rules out CHF. If abnormal, more tests needed.

12
Q
A

Know this cold

13
Q

Note which hypothalamic releasing hormones are cAMP, and which are DAG/PKC/IP3

A

Trick: cAMPing is stressful (CRH) for grown-ups (GHRH). Just remember GHIH goes with GHRH since antagonizing same pathway.

14
Q

What hypothalamic nucleus are we seeing here?

A

These are POA - we’re looking at GnRH cell bodies. These are released in a pulsatile manner - OBLIGATORY!

15
Q

Take home?

A

Kallman’s syndrome. Migration of GnRH neurons from olfactory placode to the forebrain is inhibited by the closure of the cribiform plate. Note - patients may also have cleft lip. This is X-linked.

16
Q

Oh dear. Which pathway promotes FSH/LH synthesis? Release?

BONUS: are we looking at a basophiles, or an acidophile?

A

IP3/Ca+ promotes RELEASE which makes sense….think about Ca2+ required for vesicles to dock and release…

DAG/PKC promotes SYNTHESIS

BONUS: we’re looking at a BASOPHILE since we’re talking about FSH/LH. Remember that “FLAT” from FLATPiG is basophiles (10%) while PiG is acidophiles (40%)

17
Q

Take home?

A

LH release is favored by high-frequency GnRH pulses.

FSH release is favored by low-frequency GnRH pulses.

18
Q

See the YELLOW arrow. Let’s focus on AVP for now. What kind of neurons are found here that secrete AVP? What hypothalamic nuclei do they originate from?

A

The AVP secreting cells come from magnocellular neuron, whose cell bodies originate in hypothalamic PVN and SON. They regulate WATER BALANCE (not stress).

19
Q

Green arrow. The AVP-secreting neurons here come from the __________ divison of _________ in the hypothalamus.

A

Parvocellular, PVN

20
Q

Which arrow secretes FLAT PiG?

A

Green

21
Q

Which arrow secretes a hormone that induces LACTATION?

A

Green

22
Q

Which arrow secretes a hormone that promotes milk EJECTION?

A

Yellow. Oxytosin.

23
Q

Which arrow contains tissue derived from neuro-ectoderm?

A

Green (posterior-pituitary)

24
Q

Which arrow contains glandular tissue, and secretes FLAT PiG?

A

Yellow. Anterior pituitary.

25
Q

What are these red things? Do What kind of neurons do they belong to? What will they secrete?

A

Herring bodies (axon terminals) of magnocellular neurons. If their cell bodies live in the PVN, they will secrete AVP + NP2. If their cell bodies live in the SON, they will secrete OXY and NP1.

26
Q

What are the purple dots

A

pituicytes - glial cells of post. pituitary

27
Q

To be continued starting at

A

handout page 35