A population of immature cerebellar parallel fibre synapses are insensitive to adenosine but are inhibited by hypoxia

► Adenosine has variable actions at parallel fibre synapses in immature rat cerebellum. ► Variability stems from differences in either A1 receptor properties or coupling to effectors. ► Parallel fibre synapses insensitive to adenosine are depressed by hypoxia, but not by A1 receptor activation.