Endo-Rx

Question 1

Describe exact steps regarding how steroid hormones work in signaling pathway

Answer 1

steroid hormones freely diffuse intracellularly

• > binds to intracellular receptor
• > CONFIRMATIONAL CHANGE of intracellular receptor so now DNA binding domain is EXPOSED
• > steroid-receptor complex now binds to DNA
• > gene expression regulation

Question 2

Beta blockers in diabetes. Why should I be concerned?

Answer 2

Beta blockers can

• beta1 selective blockers (A-M) are more preferred than non-selective beta blockers. Apparently B2 is more associated with gluconeogenesis. (This is in UWORLD)

Question 3

AngII mediates efferent arteriole constriction through what pathway?

Answer 3

Gq

• > Phospholipase C
• > IP3
• > increased intracellular Ca2+
• > smooth muscle constriction

Question 4

Compare location: Branchial cleft cyst vs. thyroglossal ductal cyst

Answer 4

thyroglossal ductal cyst: anterior neck

branchial cyst: lateral neck

Question 5

Total body potassium level in DKA?

Answer 5

decreased: total body K+ loss by osmotic diuresis

* However, serum K+ may look as normal or hyperkalemic due to K+/H+ activity

Question 6

Is polydypsia/polyura seen in Cushing? why or why not?

Answer 6

Yes.

Cushing can cause hyperglycemic state (cortisol acts as counter-regulatory hormone for insulin, promoting lipolysis and gluconeogenesis) => osmotic diuresis

Question 7

Anatomy: venous drainage of

• right adrenal gland
• left adrenal gland

Answer 7

• right adrenal gland: IVC
• left adrenal gland: left renal vein
• this is pretty much equivalent to pampiniform plexus of spermatic cord => why left varicocele is more
  common
• this rule also applies to ovarian veins

Question 8

Patient with poor diet, signs of hypocalcemia

: what is going on? how calcium regulatory hormones affected?

Answer 8

vitamin D deficiency

=> increased 1-alpha reductase activity, PTH to compensate for low calcium

Question 9

Liver

• which GLUT?
• Is this GLUT insulin dependent or independent?
• Does this GLUT have high affinity or low affinity to glucose?

Answer 9

• GLUT 2
• Insulin independent: liver takes up glucose and make glycogen regardless of insulin stimulation
• low affinity to glucose
• think like this: if it has high affinity, it will take up glucose too much although it doesn’t need glucose that much (as it has store glycogen already)

Question 10

What endocrine disease can be caused by demeclocycline?

Answer 10

nephrogenic DI

• interesting: demeocycline is indicated for SIADH as it works as ADH antagonist. It can cause nephrogenic DI sort of opposite presentation of SIADH