KCS

Blood vessel is a pivotal source to deliver oxygen and nutrients to living organism, therefore, the formation of a functional vascular system is a prerequisite to fulfill the metabolic demands of the mammalian embryo. In developing brain, tissue-specific differentiation of endothelium is observed in the blood-brain barrier (BBB). Brain microvessels are formed mainly through angiogenic process from the preexisting perineural vascular plexus. Then brain microvessels are differentiated and matured into the BBB. The development of the BBB is also deeply associated with oxygen tension which is involved in the coordinated regulation of brain angiogenesis and barriergenesis. After brain angiogenesis, reoxygenation of astrocytes renders a significant driving force for the maturation of the BBB during brain development through oxygen-regulated proteins. Collectively, we suggest that the development of BBB in brain is mainly regulated by appropriated responses to oxygen availability at both early developmental and differentiating stages.