Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
37 Cards in this Set
- Front
- Back
|
motor neurons from the myenteric plexis activate what?
|
interneurons
|
|
|
what neurotransmitter do interneurons secrete?
|
substance P
|
|
|
substance P causes the stimulates other neurons to release what?
|
AcH and VIP
|
|
|
T or F:
There are no CFTR channels in the intestine? |
F!
they let chloride into the lumen |
|
|
how does bicarb get from the blood to the enterocyte?
|
through a Na/bicarb pump
|
|
|
how does the bicarb get from the enterocyte to the lumen?
|
through Cl/bicarb antiport
|
|
|
where are cells in zone 1 of the liver located?
|
around the portal vein (periportal hepatocytes)
|
|
|
where are cells in zone 2 of the liver located?
|
around the central vein (periperipheral hepatocytes)
|
|
|
what are the functions of zone 1 in the liver?
|
AA metabolism
gluconeogenesis glycogen degradation ureagenesis FA oxidation |
|
|
what are the functions of zone 2 in the liver?
|
glycolysis
glycogenesis ketogenesis glutamine synthesis xenobiotic metabolism |
|
|
where are the OATP-1, OATP-2, and the CATP-1 carriers located?
|
they are transport proteins in the liver that carrier anions and cations
|
|
|
what is responsible for Xenobiotic metabolism?
|
cytochrome P-450 enzyme
|
|
|
where is cytochrome P450 found
|
in smooth ER in the liver
|
|
|
what is involved in the phase I rxn of cytochrome P450?
|
hydroxilation, dealkylation and dehalogenation
|
|
|
what does phase II rxn of cytochrome 450 involve?
|
product is conjugated to glucuronate, sulfate, and glutathione
|
|
|
what gets rid of biliruben?
|
liver
|
|
|
how is biliruben taken into the enterocyte and how does it leave?
|
it is taken in through channels or the OATP, it is taken up and modified in the ER, and it is secreted into the bile duct through the MRP2 (multi drug resistant proteins)
|
|
|
what happens to unconjugated biliruben?
|
it is taken up, conjugated to glucuronic acid and secreted in the feces and urine
|
|
|
non-de-novo synthesis of cholesterol relies on what?
|
the liver taking up chylomicrons and LDL from the portal blood
|
|
|
how does the liver do de-novo synthesis?
|
acetyl-Co -->HMG-CoA-->mevalonate-->cholesterol
HMG-CoA reductase convertes HMG-CoA to mevalonate |
|
|
after packaging how is cholesterol secreted?
|
HDL or VLDL
|
|
|
what do statins do?
|
the block the HMG-CoA reductase enzyme and messes up muscle metabolism
|
|
|
how are fat soluble vitamins carried in portal blood?
|
in chylomicrons
|
|
|
ADEK are removed from blood by what?
|
hepatocytes
|
|
|
what is the cell turn-over rate in the intestine?
|
4-5 days
|
|
|
what are located inside microvilli
|
vessels and lacteals
|
|
|
what part of the microvilli is involved in absorbtion?
|
upper 1/3
|
|
|
what is the layer in the intestine called that is not affected by segmentation?
|
the unstirred layer
|
|
|
proteins that make up the tight junctions in the intestine that block water movement are called what?
|
claudins
|
|
|
bacteria and viruses can effect water movement in the intestine how?
|
affects paracellular movement by affecting claudin proteins
|
|
|
how is transcellular absorbtion of water accomplished in the intestine?
|
linked to nutrient absorption by SGLT1
|
|
|
how does potassium, chloride, and bicarb move in the duodenum and jejenum?
|
paracellularly
|
|
|
in the duodenum and jejenum how are AA and glucose transported?
|
cotransported with Na
|
|
|
what pumps in the duodenum and jejunum are functioning in the fasting state?
|
Cl/bicarb and Na/H
|
|
|
which pumps are functioning in the duodenum and jejunum are functioning in the fed state?
|
Na/glucose/aa pump
|
|
|
the Na/glucose/aa pump in the duodenum and jejunum is dependent on what?
|
the Na/K pump
|
|
|
how much calcium do we take in each day?
how much calcium is absorbed/day? how much calcium is secreted in the intestine? what is the net absorption of calcium/day? |
1000mg
500mg 325mg 175mg |
