Blood Vessels Research Paper

There are three major types of blood vessels: arteries, capillaries, and veins, and they all differ in their histological features. Arteries are the thickest blood vessels of the three. They have a tunica intima which has an internal elastic lamina and endothelium (simple squamous epithelium), a tunica media, an external elastic lamina, and a tunica externa or adventitia. Because arteries are built to withstand pressure and stretching, they could be elastic or muscular arteries. It depends on the type of artery which tells us what they are primarily made of (although they all are mainly similar in structure). Their tunica media is much thicker than any other blood vessel. It consists of many collagen fibers and a few elastic fibers dispersed

The reason behind this is because veins have to withstand the pressure of blood being released by the arteries. It also has the similar features as arteries, except that there is no external elastic lamina. An endothelial layer also surrounds the lumen in the tunica intima of a vein. Sometimes there may be an internal elastic lamina seen, if the vein is larger or thicker. Lastly, capillaries are the thinnest of the blood vessels and connect the arteries and veins. They are made of pericytes and an endothelial layer, also possibly a basement membrane. The reason for this thinness is to allow for the exchange of gases and nutrients to flow in and out of the

The histology for essential benign hypertension, however, affects the smaller arteries and arterioles. The interlobular arteries experience a thickening of the tunica intima and the elastic lamina duplicates itself. Pathological changes in patients that suffer from this type of hypertension, that occur in the heart and brain, could be subjected to arterosclerosis. This could be fatal because it can cause an aneurysm to rupture and result in cardiac or cerebral damage. Those who suffer from accelerated or malignant hypertension have fibrous endarteritis in the interlobular arteries of their kidneys. It also results in fibrinoid necrosis in the walls of some efferent glomerular arterioles. In malignant hypertension, ischemic damage to the kidneys may also occur (Weller,