Stimulation of Angiogenesis by Adenosine on the Chick Chorioallantoic Membrane

The effect of adenosine on the vascular density of the chick chorioallantoic membrane was studied. Elvax polymer pellets containing 0.2–3.0 mg of adenosine were placed on the chorioallantoic membrane of 10-day embryos. Control pellets containing mannitol were placed at least 1 cm away. After 4 days the membrane was formalin-fixed and removed. A thin plastic coverslip, inscribed with concentric circles (4–8 mm in diameter), was placed over the pellet. A vascular density index was estimated at 20x by counting the number of intercepts between vessels and the inscribed circles. Adenosine stimulated a dose-dependent increase (p