Library · Cellular process
How the body builds new blood vessels
Make it clearer
Angiogenesis is the way the body builds new blood vessels: it does not put them together from scratch, it makes them sprout from a vessel that was already there. It is a new branch off the trunk, not a new tree.
It is worth distinguishing it from its cousin, vasculogenesis. In vasculogenesis, precursor cells that come from the bone marrow reach the damaged tissue and build the vessel from scratch. Both happen when a wound heals, but they are not the same thing.
What switches angiogenesis on is tissue in trouble. When it runs short of oxygen, which is called hypoxia, or when lactate and redox stress build up, macrophages, the cleanup cells that arrive at the area, release a messenger called VEGF, vascular endothelial growth factor.
VEGF signals the endothelium, the layer of cells that lines vessels on the inside. Those cells start migrating toward the area that needs them, building tubes that sprout from the postcapillary venules, the finest vessels of the venous system.
And they do not stay as dead ends: those tubes end up plugging into the circulation that already existed, and blood starts running through them.
In brief
Angiogenesis is the growth of new vessels that sprout from vessels that already exist.
A new branch off the trunk, not a new tree.
It is not vasculogenesis, where bone marrow precursors build the vessel; both happen in a wound.
Hypoxia, redox stress and lactate trigger it by making macrophages release VEGF.
VEGF makes capillary endothelium migrate and form tubes from postcapillary venules.
Those tubes end up connecting to the circulation that was already there.
Sources (1)
- National Center for Biotechnology Information, StatPearls PublishingHyperbaric Oxygen Effects on Angiogenesis, StatPearlsPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
Updated