AQP4 and stroke disorder: There is also evidence that excitatory amino acid transporters that take up extracellular glutamate, released as a result of spreading depolarisation or neuronal lysis after stroke, form complexes with aquaporin 4 (AQP4), the water transport channel constitutively expressed by astrocytes, which facilitate co-transport of water alongside glutamate, leading to astrocytic swelling [75–77].