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Dennesse Mari M. Uy posted an update in the group
MT 30 – GH (Lec) 4 years ago Hello! I am sharing this to everyone!
Histology, Blood Vascular System – StatPearls – NCBI BookshelfBlood vessels are fundamental components of the cardiovascular system, responsible for the dynamic transportation of matter and blood products to every cell in the body. The vascular network begins at the outlets of the heart, courses the entire body, and returns at the major venous inlets of the heart. This complex vascular highway functions to deliver blood cells, nutrients, oxygen, and pharmacological agents to tissue. Just as blood vessels direct material towards the tissue, they also facilitate the removal of cellular byproducts, carbon dioxide, and toxic chemicals from the tissue. Histologically the vasculature system is separated into macro vasculature and microvasculature. The macro vasculature being any vessel observable with the naked eye, and the microvasculature being vessels that are less than 100 microns.
In these two systems, there are tissues found which housed an important type of cell called pericytes. Recent researches have found the importance of these cells in blood vessels especially that demands of tissues varies according to anatomical area.
Pericytes are found in both venules and capillaries and they are found in the basement membrane of these vessels. It is also known as Rouget cells and is important for the regulation of maturing endothelial cells. They help for the maintenance of microvascular blood flow, clearing of cellular debris and keeping the blood-brain barrier functionality. For neuroendocrine unit signalling, pericytes also has its role.
Aside from the discussion on pericytes, the article also talked about tissue preparation which is what I am personally curious about since the beginning of this course. It provides a thorough discussion on how to correctly prepare specimen for better visualization of tissues.
Finally, it describes the appearance of blood vessels in both low and high magnifications in light microscope and electron microscope. Specifically, the morphological changes of endothelial cells are seen when viewed in an electron microscope. This is due to shear stress, thus they appear elongated as the width decreases. In higher magnification, pericytes are mentioned to be visible.
Citation:
Taylor AM, Bordoni B. Histology, Blood Vascular System. [Updated 2021 May 10]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK553217/