Questions Flashcards
Company develops irreversible antagonist of neuropeptide Y. What side effects?
a. nothing, NPY only stimulates appetite
b. constipation b/c increased water reabsorption
c. diarrhea b/c increased small intestine motility
d. steatorrhea [fat in stool]
e. C and D
f. B and D
answer = E
Of prolactin, growth hormone, IGF-1, somatostatin – which act on JAK/STAT coupled receptors?
- prolactin
- GH
- IGF-1
not somatostatin
What does acute abdominal pain represent in terms of timing in menstrual cycle?
ovulation
What levels of LH/FSH/estrogen in menopause?
- at menopause loss of functioning follicles in ovaries
- get high LH/FSH but low estrogen
Effect of test protein meal on acid output in patient with zollinger-ellison?
- normally protein meal causes increased gastrin secretion which causes increased acid
- since the gastrin she is getting is already super high from an ectopic source, G cells are super inhibited so the protein will have no effect on acid secretion
What happens to gastric mucosa in zollinger-ellison?
- hypertrophy of gastric mucosa since high gastrin stimulates growth of ECL etc
what is gastrin and acid level in patient taking proton pump inhibitor or H2 blocker?
- high gastrin [no neg feedback]
- low acid
What is normal affect of secretin on gastrin?
secretin normally inhibits gastrin secretion by G cells
3 signs of VIPoma? why?
- watery diarrhea
- hypokalemia
- achlorrhydia
What is action of VIP?
- stimulates fluid and electrolyte secretion by intestine/pancreas/liver
- inhibits acid secretion [by inhibiting G cells release of gastrin]
- smooth muscle relaxation [peristalsis, sphincters]
3 things that inhibit G cells release of gastrin
- secretin
- VIP
- low pH in stomach
What is dumping syndrome?
- dizziness, sweating, palpitations after eating
- ingested food moves quickly into duodenum and is hypertonic so draws large volume fluid and electrolytes into gut
- causes drop in BP
Why would lack of stomach cause iron-deficiency?
- ferrous [2+] iron is more soluble and absorbable in intestine than ferrric [3+]
- 3+ is the kind found in food
- 3+ gets converted to 2+ in acidic stomach so get more iron that is able to be absorbed
- if no stomach this doesn’t happen
Why would lack of stomach cause metabolic acidosis?
- in intestinal phase of digestion: HCO3 secreted into lumen and get equivalent H+ secreted into blood stream
- normally this is balanced out in stomach where H+ in lumen and HCO3 to blood stream
- if no H+ production you have none of the HCO3 entering blood stream so get metabolic acidosis
What 4 things injected intraveneously could cause increase in bile secretion? how to determine between them?
- CCK [also causes gall bladder contraction]
- gastrin because of homology to CCK [also causes acid secretion and gall bladder contraction]
- secretin [also cause pancreatic secretion]
- bile salts [just increase bile flow]
What causes gall bladder contraction?
CCK
Is fructose absorption Na dependent or independent?
independent
What causes release of PTH?
low ionized [free] Ca
What are effects of PTH?
- increased Ca and PO4 from bone resorption
- in kidney: more reabsorption Ca, excretion PO4, hydroxylation 25OH-D to active form
- in intestine: vid D causes increased Ca absorption
What happens to serum PO4, PTH, and 1,25 OH D [active D] in hyperparathyroidism?
- low PO4
- high PTH
- high 1, 25 OH D
What happens to serum PO4, PTH, and 1,25 OH D [active D] when you ingest too much vit D?
- high PO4
- low PTH
- high 1, 25 OH D
What are actions of Vit D
- increases absorption PO4 and Ca from intestines
What happens to serum PO4, PTH, and 1,25 OH D [active D] when you have bone destruction?
- high PO4
- low PTH
- unchanged vit D
What happens to serum PO4, PTH, and 1,25 OH D [active D] from PTH-rp [parathyroid related protein]?
- low PO4
- low PTH
- high vit D
PTH-rp is homologous to PTH so will bind PTH receptor and have same functions at PTH but cause low PTH due to neg feedback. PTH-rp also can increase cancer growth/survival
What is dexamethasone suppression test?
- for pt with high ACTH
- give dex, if ACTH coming from pituitary adenoma, it will bind ACTH and lower cortisol even in cushings
- if ectopic ACTH, dex will have no effect on ACTH and thus not lower cortisol
