Minerals, Elements Skildog Flashcards
Calcium is active when it combines with what?
Calmodulin
What molecule inhibits calcium channels?
Calcineurin
What does the calcium/calmodulin complex do to glycogen synthase and glycogen phosphorylase?
Inhibits glycogen synthase! And activates glycogen phosphorylase! Want to liberate glucose
Calcium inhibits the uptake of what element?
Phosphorous
The more calcium you ingest, the more of what you are going to poop out?
Bile salts and fat
Magnesium transporter of brush border?
Saturable or unsaturable?
TRPM6
Saturable
Gitelman Syndrome
Mutation of SLC12A3 (Na Cl transporter)
Hypomagnesemia
Hypokalemia
Hypocalciuria
Only anion secreted by GI cells
Chloride
Refeeding syndrome can deplete what elements?
Potassium and phosphorous
What do you use to tx hyperphosphatemia from renal failure?
Antacids! Because Mg+, Al+ and Ca++ all inhibit phosphorous absorption
What regulates the body’s amount of phosphorous?
KIDNEY
Not absorption
What does aldosterone do to urinary K+ concentration?
Increases it because we are keeping sodium so we get rid of potassium
Transporter that brings iron into enterocyte
DMT1
What enzyme oxidizes iron from Fe2+ to Fe3+?
Ceruloplasmin = Hephaestin
What element does ceruloplasmin require?
Copper
So if you have a _____________ deficiency, you have a functional _______deficiency
Copper
Iron
Main store of iron
liver
Regulation or iron uptake. Tell me about how it works.
Hepcidin
Iron stores in liver are high…hepcidin is produced andbinds to ferroportin causing its degradation…this means that iron can not get into the blood stream
What maintains iron in its reduced state in the lumen?
Vitamin C
Iron inhibits the absoprtion of what element?
Zinc
Chronic hemochromatosis
Hepcidin mutation! Horrible iron accumulation
Copper destined for other tissues enters the blood through what enterocyte transporter?
ATP7A
Menkes Kinky Hair Syndrome
Mutation in ATP7A…Hypothermia, hypotonia, poor feeding, FTT, seizures…Can’t get copper into the blood! Stuck in enterocyte
Wilson Disease
Mutation of ATP7B…liver specific copper transporter on canicular membrane of hepatocyte…normally transports excess copper into the bile for excretion…When defective, copper accumulates and leaks out unbound to ceruloplasmin
Hallmark: Kayser-Fleischer Ring in Eye
