Lipoproteins
This lipoprotein is produced in intestinal cells and transports dietary triglycerides from the gut to muscle, adipose tissue and the liver.
What is a chylomicron?
Following vessel injury, platelets release thromboxane A₂ and serotonin, producing this immediate narrowing response.
What is vascular spasm?
his local control mechanism keeps organ blood flow relatively constant despite changes in perfusion pressure.
What is autoregulation?
This imbalance between myocardial oxygen supply and oxygen demand is the underlying basis of ischaemic heart disease.
What is myocardial ischaemia?
This enzyme is located on the surface of capillary endothelial cells and breaks down triglycerides within chylomicrons and VLDL, releasing free fatty acids.
What is lipoprotein lipase?
This platelet-released molecule increases the adhesiveness of nearby platelets and promotes platelet aggregation.
What is ADP?
When intraluminal pressure rises, arteriolar wall stretch causes vasoconstriction and increased resistance through this pressure-sensitive local response.
What is the myogenic response?
This acute change in an atherosclerotic plaque exposes thrombogenic material and commonly triggers formation of a superimposed coronary thrombus.
What is plaque rupture or plaque erosion?
This HDL surface apoprotein helps collect cholesterol from foam cells during reverse cholesterol transport.
What is ApoA-I?
In the extrinsic pathway, tissue factor, factor VIIa and calcium activate this clotting factor.
What is factor X?
During increased myocardial activity, ATP breakdown produces this metabolite, which is a major mediator of coronary vasodilation and active hyperaemia.
What is adenosine?
A large non-occlusive coronary thrombus or major intraplaque haemorrhage can produce this infarction pattern, which usually presents without ST elevation.
What is a subendocardial infarction, or NSTEMI?
This intestinal cholesterol transporter is inhibited by ezetimibe, reducing cholesterol absorption and indirectly increasing LDL-receptor expression.
What is NPC1L1?
This endothelial enzyme converts plasminogen trapped within a clot into plasmin, allowing fibrin to be digested.
What is tissue plasminogen activator, or tPA?
In cerebral tissue, increased metabolism raises this gas, producing carbonic acid and H⁺, lowering extracellular pH and causing cerebral vasodilation
What is carbon dioxide, or CO₂?
Following complete coronary artery occlusion, myocardial necrosis begins in this region because it is furthest from the epicardial arteries and exposed to high intramyocardial pressure.
What is the subendocardial zone?
This protein normally promotes degradation of LDL receptors; inhibiting it increases receptor recycling and enhances clearance of circulating LDL.
What is PCSK9?
This naturally occurring anticoagulant, produced by mast cells and basophils, enhances antithrombin III activity against thrombin and activated factor X.
What is heparin?
This endothelium-derived mediator is produced from L-arginine by eNOS, activates soluble guanylate cyclase in vascular smooth muscle, increases cGMP and causes relaxation.
What is nitric oxide, or NO?
Even during progression toward a transmural infarct, this very thin innermost layer immediately beneath the endocardium may remain viable because it receives oxygen by direct diffusion from the ventricular chamber.
What is the subendocardial rim of viable myocardium?