The internal elastic lamina or internal elastic lamella is a layer of elastic tissue that forms the outermost part of the

tunica intima The tunica intima (Neo-Latin "inner coat"), or intima for short, is the innermost tunica (biology), tunica (layer) of an artery or vein. It is made up of one layer of endothelium, endothelial cells (and macrophages in areas of disturbed blood flo ...

blood vessels Blood vessels are the tubular structures of a circulatory system that transport blood throughout many animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the tissues of a body. They also take waste an ...

. It separates

from

tunica media The tunica media (Neo-Latin "middle coat"), or media for short, is the middle tunica (layer) of an artery or vein. It lies between the internal elastic lamina of the tunica intima on the inside and the tunica externa on the outside. Artery The ...

Histology

It is readily visualized with light microscopy in sections of muscular arteries, where it is thick and prominent, and arterioles, where it is slightly less prominent and often incomplete. It is very thin in veins and venules. In elastic arteries such as the

aorta The aorta ( ; : aortas or aortae) is the main and largest artery in the human body, originating from the Ventricle (heart), left ventricle of the heart, branching upwards immediately after, and extending down to the abdomen, where it splits at ...

, which have very regular elastic laminae between layers of smooth muscle cells in their

, the internal elastic lamina is approximately the same thickness as the other elastic laminae that are normally present. There is small amount of subendothelial connective tissue between

basement membrane The basement membrane, also known as base membrane, is a thin, pliable sheet-like type of extracellular matrix that provides cell and tissue support and acts as a platform for complex signalling. The basement membrane sits between epithelial tis ...

of endothelial cells and internal elastic lamina. Reduplication of internal elastic lamina can be seen in elderly individuals due to intimal fibroplasia, which is part of the

aging Ageing (or aging in American English) is the process of becoming Old age, older until death. The term refers mainly to humans, many other animals, and fungi; whereas for example, bacteria, perennial plants and some simple animals are potentiall ...

process.

Associated pathologic conditions

*Damage in giant cell arteritis leads to microaneurysms. Demonstration of fragmentation in this layer by elastin- van Gieson stain aids in diagnosis of giant cell arteritis. It stains

muscle Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contra ...

tissue in yellow,

connective tissue Connective tissue is one of the four primary types of animal tissue, a group of cells that are similar in structure, along with epithelial tissue, muscle tissue, and nervous tissue. It develops mostly from the mesenchyme, derived from the mesod ...

in red and elastic structures (like internal elastic lamina) in black color. * In chronic allograft nephropathy, disruption or reduplication of internal elastic lamina can be observed, which causes narrowing of the lumen and downstream ischemia. * In fungal rhinosinusitis, the organism has predilection for internal elastic lamina during phase of spread.

References

{{DEFAULTSORT:Internal Elastic Lamina Angiology