Introduction Dictyostelium discoideum Ideal microenvironments for purinergic signaling 1 4 3 4 5 6 7 8 9 10 11 12 5 6 Purinergic Signalling 13 14 20 An ideal microenvironment paradigm for extracellular purinergic signaling: the synapse 21 23 24 25 26 2+ 2+ 11 2+ + 2+ 2+ + 2+ + 2+ + 2+ + 2+ 2+ 9 10 21 23 Conclusions and future directions 26 Purinergic Signalling