Summary
Aquaporins are intrinsic membrane proteins involved in water transport in fluid-transporting tissues. In the brain, aquaporin-4 (AQP4) is expressed widely by glial cells, but its function is unclear. Extensive basic and clinical studies indicate that osmolarity affects seizure susceptibility, and in our previous studies we found that AQP4 -/- mice have an elevated seizure threshold in response to the chemoconvulsant pentylenetetrazol. In this study, we examined the seizure phenotype of AQP4 -/- mice in greater detail using in vivo electroencephalographic recording. AQP4 -/- mice were found to have dramatically longer stimulation-evoked seizures following hippocampal stimulation as well as a higher seizure threshold. These results implicate AQP4 in water and potassium regulation associated with neuronal activity and seizures.
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Binder, D.K., Yao, X., Verkman, A.S., Manley, G.T. (2006). Increased seizure duration in mice lacking aquaporin-4 water channels. In: Hoff, J.T., Keep, R.F., Xi, G., Hua, Y. (eds) Brain Edema XIII. Acta Neurochirurgica Supplementum, vol 96. Springer, Vienna. https://doi.org/10.1007/3-211-30714-1_80
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DOI: https://doi.org/10.1007/3-211-30714-1_80
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