Fig. 7From: Adenosine receptor signaling: a key to opening the blood–brain doorA model: Adenosine modulation of blood brain barrier (BBB) permeability. Endothelial cells lining the brain vasculature express adenosine receptors (ARs) and CD39 and CD73. In the presence of cell stress/inflammation or tissue damage (a), ATP is released and is rapidly converted to ADP and AMP by CD39 (b) and AMP is converted to adenosine by CD73. c Adenosine binds to its receptor/s (A1 or A2A) on BBB endothelial cells (d), the activation of which induces reorganization of actin cytoskeleton in BBB endothelial cells, resulting in tight and adherens junction disassembly (e), increasing paracellular permeabilityBack to article page