AQP4 and edema: AQP4 has been established as a critical therapeutic target for cerebral edema, where it mediates astrocytic cytotoxic edema in the acute phase but nevertheless alleviates vasogenic edema during the chronic phase.[64, 65, 66, 67, 68] We observed that LPS treatment significantly reduced the polarized distribution of perivascular AQP4 at 24 h post‐induction, concomitant with downregulated AQP4 protein expression.