Endothelial Cell Function and Dysfunction Quiz

Blood Vessels

• Arteries with concentric rings of medial smooth muscle cells are called muscular arteries.
• The main component of the capillary wall is a single layer of endothelial cells.
• Loss of aortic elastic tissue in a large artery can result in aneurysm formation.
• Veins have relatively poorly developed medial layers.
• A key feature of the vascular endothelium is its ability to produce nitric oxide (NO) synthase.

Endothelial Function

• Nitric oxide (NO) is synthesized from L-arginine through the action of NO synthase.
• The activated state of the endothelium is associated with increased activity.
• Active compounds synthesized by the endothelium, such as NO and prostacyclin, inhibit platelet aggregation.
• Oxidative stress plays a role in endothelial dysfunction.
• Endothelial dysfunction contributes to atherosclerosis.

Atherosclerosis

• A characteristic feature of atheromatous plaque formation is the accumulation of modified lipoproteins.
• The main process leading to lipoprotein modification is oxidation.
• Endothelial dysfunction is associated with hypertension, diabetes, and hypercholesterolemia.
• Endothelial dysfunction provides a window into cardiovascular risk.

Lipoproteins and Endothelial Function

• Modified LDLs are removed from the bloodstream by macrophages.
• Endothelial damage promotes clotting by inducing a procoagulant state.
• Oxidized LDLs are mainly produced by free radicals generated by endothelial cells.
• Endothelial function can be assessed in vivo using flow-mediated dilation (FMD) and other methods.
• Endothelial dysfunction can be assessed in patients with cardiovascular disease.

Endothelial Repair and Inflammation

• Endothelial cells play a role in vascular repair by producing growth factors and adhesion molecules.
• Exposure to certain mediators can cause endothelial cells to become activated.
• Thrombomodulin, produced by endothelial cells, inhibits thrombin and activates protein C.
• Inflammation disrupts the balance between procoagulant and anticoagulant properties of the endothelium.
• Leucocyte extravasation involves rolling, adhesion, and migration through the endothelium.
• Injury or exposure to certain mediators can activate endothelial cells.

Miscellaneous

• The endothelium is NOT a constituent of the vascular wall.
• The endothelium in blood vessels regulates vascular tone, blood pressure, and immune responses.
• Endothelial cells are involved in vascular repair and inflammation.
• The key regulator of vascular tone is nitric oxide (NO).
• Endothelial dysfunction can be improved through lifestyle changes and pharmacological interventions.