What is the middle muscle layer in a blood vessel called?

Answer 1

The three layers of the arterial wall are, from outside to inside, the adventia, the media and the intima. A flat layer of cells, called endothelial cells, forms a boundary between the blood in the lumen, or cavity, and the innermost layer of the arterial wall. Its called tunica intima "The tunica media is the middle layer in a blood vessel wall and is composed predominantly of smooth muscle reinforced by organised layers of elastic tissue which form elastic laminae. The tunica media is particularly prominent in arteries, being relatively indistinct in veins and virtually non-existent in very small vessels. The tunica media also contains autonomic nerves. In vessels which are close to the heart, receiving the full thrust of the systolic pressure wave, elastic tissue is very well developed, hence the term elastic arteries. In muscular arteries and arterioles the prominent elastic lamina just below the tunica intima is termed the internal elastic lamina."

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