Hyaluronate in vasculogenesis.

Limb buds of chicken embryos contain within the peripheral mesoderm an avascular zone that is rich in hyaluronic acid. Epithelial tissues that synthesize large amounts of hyaluronic acid relative to other glycosaminoglycans caused avascularity when implanted into normally vascular wing mesoderm. Epithelia that synthesize little hyaluronic acid did not cause avascularity. Elvax implants containing hyaluronic acid caused the formation of avascular zones, whereas similar implants containing other glycosaminoglycans did not give rise to avascular zones. Hyaluronic acid may thus play a role in determining the location of blood vessels in the embryo.