Cholesterol and Atheroma Flashcards
what are the 4 types of lipoproteins?
high density lipoprotein (apoA I and apoA II)
low density lipoprotein (apoB-100)
Very low density lipoprotein (apoB-100)
chylomicrons (apoB-48)
basic structure of lipoproteins
hydrophobic core
hydrophilic coat layered with apoproteins
where do ApoB containing lipoproteins deliver TAGs for ATP biogenesis?
Muscle cells
where do ApoB containing lipoproteins deliver TAGs for storage?
adipocytes
where are apoB-100 lipoproteins made?
liver
where are apoB-48 lipoproteins made?
intestine
what happens to some LDL in the artery?
it is oxidised into OXLDL
what do macrophages do to OXLDL?
convert it to cholesterol- laden foam cells
which forms fatty streaks
what occurs due to the presence of fatty streaks in the artery?
inflammatory substances are released from various cells and this causes proliferation of smooth muscle cells and causes the deposition of collagen
what does a atheromatous plaque contain?
fibrous cap and lipid core
where is HDL produced and where does it mature?
it is made in the liver (initially as ApoA-I), then matures in the plasma
what do simvastatin and atorvastatin act as?
competitive inhibitors of HMG-CoA reductase
why is HMG-CoA important in the synthesis of cholesterol?
it is important in the rate limiting step
give one example when statins are useless
if the patient has homozygous familial hypercholesterolaemia
what other positive effects do statins have?
decreased inflammation, reversal of endothelial dysfunction, decreased thrombosis, stabilisation of atherosclerotic plaques
