Atherosclerotic plaques form in which tunica of large and medium arteries?

Atherosclerotic plaques form in which tunica of large and medium arteries?

• A. Adventitia
• B. Endothelium
• C. Intima
• D. Media

Answer: (C)

Atherosclerotic plaques form in the tunica intima, the inner lining of large and medium arteries. Endothelial injury or dysfunction lets lipids enter the subendothelial space, where macrophages take up lipids and become foam cells. This lipid buildup triggers inflammation and smooth muscle cells from the media migrate into the intima, proliferate, and produce extracellular matrix, creating a lipid-rich plaque that expands into the lumen. The adventitia is the outer layer and the media is the smooth muscle layer; the lesion itself is primarily in the intima.

Atherosclerotic plaques form in the tunica intima, the inner lining of large and medium arteries. Endothelial injury or dysfunction lets lipids enter the subendothelial space, where macrophages take up lipids and become foam cells. This lipid buildup triggers inflammation and smooth muscle cells from the media migrate into the intima, proliferate, and produce extracellular matrix, creating a lipid-rich plaque that expands into the lumen. The adventitia is the outer layer and the media is the smooth muscle layer; the lesion itself is primarily in the intima.