vascular system

Question 1

general good and bad lipoproteins

Answer 1

HDL (good) and LDL (bad)

Question 2

LDL apoprotein

Answer 2

B

Question 3

HDL apoprotein

Answer 3

A-1

Question 4

exogenous pathway of lipid metabolism

Answer 4

dietary triglycerides and cholsterol ingested, digested and absorbed in intestine -> chylomicron -> LP lipase to FFA (skeletal muscle, adipose tissue) and chylomicron remnant (liver and atheroma)

Question 5

endogenous pathway of lipid metabolism

Answer 5

liver degrades lipid to large and small VLDL, IDL, LDL etc. (enzymes convert to larger lipids, which then bind with proteins to travel in blood)

Question 6

reverse cholesterol transport of HDL

Answer 6

HDL breaks down by CETP (cholesteryl ester transfer protein) to LDL and VLDL

Question 7

what is first stage of atherosclerosis

Answer 7

leaky endothelium (increased permeability), causing upregulation of endothelial adhesion molecules and causing leukacyte adhesion, causing leukocytes (mainly monocytes) entering subendothelial space (intima) and causing inflammation

Question 8

development and predictability of atherosclerosis

Answer 8

doesn’t always progess or progresses having skipped stages, so unpredictable

Question 9

fatty streak formation (present in many people, including young Western)

Answer 9

foam cells form as leukocytes engulf lipids, causing adherence and aggregattion of platelets and T-cell activation

Question 10

formation of complicated atherosclerotic plaque

Answer 10

formation of necrotic core and fibrous cap due to accumulation of macrophages (susceptibility to rupture differs)

Question 11

remnant chylomicron (glycoproteins) and association with atherosclerosis

Answer 11

high levels more prone to atherosclerosis, due to driving inflammation

Question 12

what keeps an atherosclerotic plaque stable

Answer 12

because thick wall of collagen and cells which protect lumen from necrotic lipid core adjacent

Question 13

what makes an atherosclerotic plaque vulnerable

Answer 13

thin wall of collagen and cells, so if rise in BP or inflammation, can rupture and form thombus

Question 14

LDL cholesterol association with atherosclerosis and CHD

Answer 14

strong, with 20% increase in CHD risk

Question 15

what risk factors modify LDL cholesterol CHD risk

Answer 15

low HDL cholesterol, smoking, hypertension, diabetes

Question 16

HDL cholesterol association with atherosclerosis and CHD

Answer 16

protective effect

Question 17

when does HDL cholesterol tend to be lower, and what lowers it

Answer 17

low when triglycerides are high, and is lowered by smoking, obesity and physical inactivity

Question 18

total cholesterol association with CHD, and meaning

Answer 18

positive, but different in different places; bad effect of cholesterol modified by different things