Journal: Frontiers in Cellular Neuroscience
Article Title: Glutamate load fosters spreading depolarization under osmotic stress in brain slices
doi: 10.3389/fncel.2025.1722194
Figure Lengend Snippet: Mechanistic summary of swelling-induced glutamate release and neuronal receptor activation during spreading depolarization. Under physiological conditions, astrocytes maintain extracellular glutamate and osmotic homeostasis via aquaporin-4 channels (AQP4), Na + -K + -2Cl − cotransporter 1 (NKCC1) and volume-regulated anion channel (VRAC), thereby preserving normal neuronal excitability. Osmotic stress promotes astrocyte swelling which activates VRAC to release glutamate, elevating extracellular glutamate and overstimulating neuronal NMDA N-methyl-D-aspartate (NMDA), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate receptors—this cascade fosters the occurrence of spreading depolarization. Pharmacological blockade—using DCPIB (VRAC blocker), Bumetanide (NKCC1 inhibitor), TGN-020 (AQP4 inhibitor), along with NMDA antagonist MK-801 and AMPA/kainate antagonist CNQX—attenuates astrocyte swelling, reduces glutamate accumulation and alleviates spreading depolarization. The figure was created in https://BioRender.com .
Article Snippet: Another set of slices was exposed to the volume-regulated anion channel (VRAC) blocker 4-(2-Butyl-6,7-dichloro-2-cyclopentyl-indan-1-on-5-yl) oxobutyric acid (DCPIB; ; Tocris; 20 μM; n = 15).
Techniques: Activation Assay, Preserving