First published online March 24, 2005
Development 132, 803e (2005)
© The Company of Biologists Limited
Vascular network limitation
During the development of the retina, platelet-derived growth factor
released by retinal neurons stimulates the proliferation of astrocytes, which
release vascular endothelial growth factor (VEGF) to stimulate blood vessel
growth. On p. 1855,
West and co-workers describe how the developing retinal vessels provide
feedback signals that trigger astrocyte differentiation, thus downregulating
VEGF production and preventing runaway angiogenesis. In newborn mice raised in
a high-oxygen atmosphere, retinal blood vessel development is blocked,
resulting in retinal hypoxia. In this situation, report the researchers,
retinal astrocytes continue to proliferate and fail to differentiate,
indicating that retinal blood vessels usually limit their own formation by
signalling to the astrocytes. Culturing astrocytes in a low-oxygen atmosphere
reproduces these effects on astrocyte behaviour, suggesting that blood-borne
oxygen might be the signal that indirectly prevents the over-elaboration of
the vascular network. Similar feedback mechanisms may also govern
vascularisation elsewhere in the nervous system.
Related articles in Development:
- Stabilization of the retinal vascular network by reciprocal feedback between blood vessels and astrocytes
- Heloise West, William D. Richardson, and Marcus Fruttiger
Development 2005 132: 1855-1862.
[Abstract]
[Full Text]
