Klappa16.4 - Transport of cholesterol in the body
Study this deck free Add to my library
- FrontBig picture of cholesterol transportBackCholesterol does not travel freely in blood
- FrontHow is cholesterol transported in the blood?BackInside lipoproteins
- FrontMain cholesterol carriers in bloodBackChylomicrons for dietary lipids, VLDL, LDL, and HDL.
- FrontCore concept of cholesterol transportBackCholesterol moves in particles, not alone.
- FrontImportant apoprotein of chylomicronsBackApoB-48.
- FrontImportant apoprotein of LDLBackApoB-100.
- FrontImportant apoprotein of VLDLBackApoB-100.
- FrontCore concept of apoproteinsBackApo proteins act as labels that determine where lipoprotein particles go.
- FrontFunction of LDLBackDelivers cholesterol to cells.
- FrontStep 1 of LDL mechanismBackLDL carries cholesterol in blood.
- FrontStep 2 of LDL mechanismBackCells have LDL receptors.
- FrontStep 3 of LDL mechanismBackLDL receptor binds ApoB-100 of LDL.
- FrontStep 4 of LDL mechanismBackLDL is taken into the cell by endocytosis.
- FrontFraction of LDL that returns to liverBackAbout 60 percent.
- FrontCore concept of LDLBackLDL is the cholesterol delivery system.
- FrontEffect of high intracellular cholesterol on cholesterol synthesisBackIt INHIBITS HMG-CoA reductase and DECREASES cholesterol synthesis.
- FrontEffect of high intracellular cholesterol on cholesterol uptakeBackIt DECREASES LDL receptor production and DECREASES uptake.
- FrontStorage form of cholesterol in cellsBackCholesteryl ester.
- FrontEnzyme that stores cholesterol in cellsBackACAT - acyl-CoA cholesterol acyltransferase.
- FrontCore concept of cellular cholesterol regulationBackCells prevent cholesterol overload by DECREASING synthesis, DECREASING uptake, and INCREASING storage.
- FrontFunction of HDLBackRemoves cholesterol from tissues and returns it to the liver.
- FrontStep 1 of HDL reverse transportBackHDL picks up cholesterol from cells.
- FrontTransporter used for cholesterol efflux to HDLBackABCA1.
- FrontEnergy requirement of ABCA1BackATP-dependent.
- FrontStep 2 of HDL reverse transportBackHDL carries cholesterol back to the liver.
- FrontLiver receptor for HDLBackSR-B1.
- FrontStep 3 of HDL reverse transportBackHDL binds to SR-B1 receptor on liver and enters liver
- FrontCore concept of HDLBackHDL is the cholesterol cleanup system.
- FrontScavenger receptor involved in pathologyBackSR-A1.
- FrontWhat SR-A1 takes upBackModified LDL, especially oxidized LDL.
- FrontRegulation of SR-A1 uptakeBackThere is NO regulation!
- FrontCholesterol consequence of uncontrolled scavenger receptor uptakeBackExcess accumulation.
- FrontMacrophage content consequence of uncontrolled scavenger receptor uptakeBackThey fill with lipid.
- FrontMacrophage characteristic consequence of uncontrolled scavenger receptor uptakeBackThey become foam cells.
- FrontPathological structure consequence of uncontrolled scavenger receptor uptakeBackFoam cells (transformed macrophages) form atherosclerotic plaques.
- FrontCore concept of scavenger receptor pathologyBackUncontrolled LDL uptake leads to foam cell formation from macrophages and atherosclerotic plaque formation.
- FrontSource of cholesterol packaged by liverBackCholesterol comes from diet and synthesis and is packaged into VLDL.
- FrontConversion of VLDL to LDLBackLPL removes TAG from VLDL, producing cholesterol-rich LDL.
- FrontHow LDL delivers cholesterol to cellsBackThrough the LDL receptor binding ApoB-100 followed by endocytosis.
- FrontFate of cholesterol inside cellsBackCholesterol is either used for energy or stored via ACAT (Acetyl-CoA Cholesterol Acyltransferase).
- FrontFeedback effect of high intracellular cholesterolBackHigh cholesterol causes feedback inhibition - cholesterol synthesis/uptake is inhibited/decreased (↓HMG-CoA reductase/↓LDL receptor production)
- FrontRole of HDL in full pathwayBackHDL picks up excess cholesterol from cell (via ABCA1 transporter) and returns it to the liver (via binding to SR-B1 receptor on liver)).
- FrontFinal core idea of cholesterol transportBackLDL delivers cholesterol, HDL removes excess cholesterol, and cells tightly regulate cholesterol levels.
- FrontRole of VLDL in transportBackVLDL transports TAG.
- FrontRole of LDL in transportBackLDL delivers cholesterol.
- FrontRole of HDL in transportBackHDL removes cholesterol.
- FrontKey binding protein for LDL uptakeBackApoB-100.
- FrontKey transporter for cholesterol efflux to HDLBackABCA1.
- FrontKey receptor for HDL uptake in liverBackSR-B1.
- FrontKey enzyme for intracellular cholesterol storageBackACAT.
- FrontCellular response to high intracellular cholesterolBackHMG-CoA reductase decreases, LDL receptors decrease, and ACAT increases.
- FrontPathology concept of oxidized LDLBackOxidized LDL taken up by SR-A1 leads to macrophage → foam cell transformation and atherosclerotic plaque formation.
- FrontLipoprotein that delivers cholesterol to tissuesBackLDL.
- FrontEnzyme that stores cholesterol INSIDE cellsBackACAT.
- FrontTransporter that effluxes intracelleular cholesterol to HDLBackABCA1.
- FrontEffect of high intracellular cholesterol on LDL receptor levelsBackLDL receptor levels decrease → decreased LDL uptake.
- FrontWhy scavenger receptors (SR-A1) are dangerous in excessBackThey take up oxidized LDL with NO regulation, causing excess cholesterol accumulation, foam cell formation, and atherosclerotic plaque formation.
Study these 57 cards with spaced repetition. Klappa is a free flashcard app: it schedules every card with FSRS-6, studies a deck as flashcards, multiple choice, typed answers or a graded test, and imports your Anki decks. How Klappa schedules reviews.