Lipids and atherosclerosis Flashcards
what is atherosclerosis?
major risks factors?
arterial wall structure and function?
Figure 7 In order to understand AS, one must understand the structure and function of the artery.
The artery has three structural components:
adventitia (which carries blood and nerve supply to the artery itself);
media (comprised of smooth muscle, which controls vascular tone);
intima (a basement membrane covered by endothelium which regulates hemostasis, thrombosis, vascular tone and permeability).
The intima is the site of AS.
plaque formation, stage 1
fatty streak formation
Figure 10 Monocytes penetrate the intima and are transformed into macrophages and eventually cholesterol-rich foam cells. These activated macrophages scavenge and ingest oxidized low-density lipoprotein (LDL) in the subendothelial space. The progressive accumulation of lipids (intra- and extracellular) forms the fatty streak.
plaque formation - Stage 2
Fibrous Cap
Figure 11 The growing fatty streak eventually forms the lipid core, which becomes isolated by the progressive formation of a fibrous cap. The fibrous cap contains collagen, proteoglycans and activated smooth muscle cells. The sturdier the cap, the less likelihood there is of plaque rupture.
plaqe formation - stage 3?
Lipid core
Figure 12 Further lipid accumulation in the lipid core results in cell death (apoptosis).
plaque to thrombus?
Figure 13 The key event in transformation of a stable plaque to an unstable plaque is rupture, which results in either partial or complete occlusive thrombosis.
3 stages if atherosclerosis?
Atherosclerosis, the process underlying most CVD, has 3 distinct stages:
─ Initiation - during which lipids are deposited on the vessel wall
─ Progression - during which inflammation increases, plaque formation builds up in the intima, and fibrous caps are formed, increasing the potential for atheroma
─ Clinical disease - when complications result from stenosis or unstable plaque rupture, leading to myocardial infarction (MI), stroke, or death.1
LACT and ACAt found in?
LCAT - vessel
ACAT - cells
phosopholipid?
2 fatty acids and a phosophate group with alcohol derived group on the 3rd brach of glycerol
plamitic, oleic ad eicosapentaenoic?
c16, c18 and c20
saturated, monounsaturated and polyunsaturated
fredrickson classification?
1 - chylomicrons - creamy top
2 - LDL - clear
3 - IDL - turbid
4- VLDL - turbid
5 - chylomicrons and VLDL - creamy top and turbid
Familial hyperlipidemias are classified according to the Fredrickson classification which is based on the pattern of lipoproteins on electrophoresis or ultracentrifugation.[3] It was later adopted by the World Health Organization (WHO). It does not directly account for HDL, and it does not distinguish among the different genes that may be partially responsible for some of these conditions. It remains a popular system of classification, but is considered dated by many[who?].
plasma lipids?
Total Cholesterol
Total Triglyceride
HDL-cholesterol (measured)
LDL-cholesterol (calculated)
friedwald forumla?
LDL chol = Total chol – HDL chol – Trig/2.2
Fasting sample
Triglyceride < 4.5 mmol/L
LDL in familial hypercholesterolaemia?
deficiency of receptors
hetero - partial
homo - full
visceral obesity and metabolic abdnomalities?
Figure 62 The Metabolic Syndrome is characterized by the following features of dyslipidemia:
high TGs;
increased small, dense LDL;
low HDL-cholesterol;
elevated apo B;
pro-inflammatory profile.
simvastatin?
cholesterol production?
