Ion dynamics at the energy-deprived tripartite synapse
Fig 1
Compartments, ion channels and transporters included in the modelling of the glutamatergic synapse.
Shown are the three main components representing a presynaptic neuron, an astrocyte and the extracellular space (ECS). Each of these compartments also contains a synaptic compartment as indicated by the different shading and the additional box (presynaptic terminal, perisynaptic process and synaptic cleft, respectively). The largest ATP consumption in the presynaptic neuron and the astrocyte is by the Na+/K+-ATPase (NKA). At the presynaptic terminal, ATP is also needed to energize glutamate uptake into vesicles. The key transporters at the cleft are the Na+/Ca2+-exchanger (NCX) and the Excitatory Acid Amino Transporter (EAAT). NKCC1: Na+-K+-Cl−-cotransporter. KCC: K+-Cl−-cotransporter. Kir4.1: K+ inward rectifier channel 4.1.