The present invention relates to a method of increasing blood brain barrier (“BBB”) permeability in a subject. This method involves administering to the subject an agent or agents which activate both of the A1 and A2A adenosine receptors. Also disclosed is a method to decrease BBB permeability in a subject. This method includes administering to the subject an agent which inhibits or blocks the A2A adenosine receptor signaling. Compositions relating to the same are also disclosed.