ATP released from astrocytes is degraded to adenosine and activates presynaptic adenosine A2 or A1 receptors that leads to an increase or decrease in its release probability (Panatier et al. , 2011). Now the problem is:
After secretion of ATP by astrocyte:
Which mechanism is activated A2A receptor on presynaptic neuron?
Which mechanism is activated A1 receptor on presynaptic neuron?
Which mechanism determines that what kind of adenosine receptors on the presynaptic neuron (A2A , A1) should be activated in response to astrocyte adenosine secretion?