Endocrine Associations_FIRSTAID

Question 1

Name the locations of insulin-DEPENDENT Glc uptake.

Answer 1

‘BRICK L’ -
GLUT 1-5, except for GLUT-4: Brain/Schwann cells + RBC/retinal BV pericytes + Intestine small + Cornea/lens + kidney + liver

Question 2

What does the brain use for Glc metabolism in fed and starvation states? How about RBC?

Answer 2

BRAIN: Fed state (Glc), Starvation (Ketones)
RBC: Glc in both states bec they don’t have mitochondria for aerobic metabolism

Question 3

Do Glc and insulin cross the placenta?

Answer 3

Glc does cross, Insulin does NOT

Question 4

What are the processes activated by INSULIN?

Answer 4

GLYCOGENESIS 
LIPOGENESIS, Decreases lipolysis 
PROTEIN SYNTHESIS 
Activates Na+/K+ ATP-ase (Na+ retention by kidneys + cellular uptake of K+ and amino acids) 
Decreases GLUCAGON

Question 5

Why is there an INCREASED insulin response to ORAL Glc compared to IV Glc?

Answer 5

Meal -> Glucagon-like peptide 1 (GLP1 - incretin) is secreted -> INCREASES beta cell sensitivity to Glc

Question 6

What are the effects of GLUCAGON? What is it inhibited by?

Answer 6

GLYCOGENOLYSIS, GLUCONEOGENESIS, LIPOLYSIS/KETONE PRDN

Inhibited by INSULIN, HYPERGLYCEMIA, SOMATOSTATIN

Question 7

Name the locations of insulin-DEPENDENT Glc transporters.

Answer 7

GLUT-4 (Striated Muscle + Adipose) - Insulin + Exercise can upregulate/stimulate expression of GLUT4 that increases Glc uptake

Question 8

What is the most common cause of HYPERPRL-EMIA? What drug class can cause this as well?

Answer 8

Hyper-PRL secreting anterior pituitary adenoma 
Dopamine antagonists (e.g. ANTIPSYCHOTICS) + ESTROGEN (OCP, Pregnancy) can also cause this bec DA normally suppresses PRL/TSH secretion and Estrogen stimulates AP to release Prolactin

Question 9

Which endogenous anterior pituitary hormone can suppress GnRH release from the hypothalamus?

Answer 9

PRL - HYPERPROLACTINEMIA can suppress GnRH release -> Responsible for the AMENORRHEA present in HYPERPROLACTINEMIA

Question 10

Which hypothalamic hormone STIMULATES PRL + TSH release from the anterior pituitary? Which hypothalamic hormone INHIBITS PRL + TSH release?

Answer 10

Stimulates - TSH

Inhibits - DA

Question 11

When is there a paraneoplastic INCREASE in PTHrP resulting in HYPERCALCEMIA, HYPOPHOSPHATEMIA, PHOSPHATURIA?

Answer 11

SQUAMOUS CELL CARCINOMA (lung) + RENAL CELL CARCINOMA

Question 12

What are the 3 stimuli of INCREASED PTH SECRETION?

Answer 12

1. HYPOCALCEMIA
2. HYPERPHOSPHATEMIA
3. HYPOMAGNESIA - although very severely low Mg2+ will induce PTH secretion

Question 13

What are some cases in which a pt will have LOW MG2+ that can elicit PTH-mediated hypercalcemia?

Answer 13

VOLUME LOSS (Diarrhea) 
DRUGS: Diuretics, Aminoglycosides, Alcohol abuse

Question 14

When is there a paraneoplastic INCREASE in PTHrP resulting in HYPERCALCEMIA, HYPOPHOSPHATEMIA, PHOSPHATURIA?

Answer 14

SQUAMOUS CELL CARCINOMA (lung) + RENAL CELL CARCINOMA

Question 15

What are the 3 stimuli of INCREASED PTH SECRETION?

Answer 15

1. HYPOCALCEMIA
2. HYPERPHOSPHATEMIA
3. HYPOMAGNESIA - although very severely low Mg2+ will induce PTH secretion

Question 16

What are some cases in which a pt will have LOW MG2+ that can elicit PTH-mediated hypercalcemia?

Answer 16

VOLUME LOSS (Diarrhea) 
DRUGS: Diuretics, Aminoglycosides, Alcohol abuse

Question 17

In which cancers do HOMER-WRIGHT rosettes present on histology?

Answer 17

NEUROBLASTOMA (most common adrenal tumor of children

Question 18

What is the most common tumor of the adrenal medulla in children

Answer 18

NEUROBLASTOMA

Question 19

What are the diagnostic neuroendocrine tumor markers to diagnose NEUROBLASTOMA?

Answer 19

BEBESIN +, NEURON-SPECIFIC ENOLASE +

Question 20

N-myc ONCOGENE overexpression is most commonly associated with which tumor?

Answer 20

NEUROBLASTOMA