caa a22 4500 606202536 CHVBK 20210128100953.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00429-014-0767-z doi (NATIONALLICENCE)springer-10.1007/s00429-014-0767-z Deletion of aquaporin-4 increases extracellular K+ concentration during synaptic stimulation in mouse hippocampus [Elektronische Daten] [Nadia Haj-Yasein, Cecilie Bugge, Vidar Jensen, Ivar Østby, Ole Ottersen, Øivind Hvalby, Erlend Nagelhus] The coupling between the water channel aquaporin-4 (AQP4) and K+ transport has attracted much interest. In this study, we assessed the effect of Aqp4 deletion on activity-induced [K+]o changes in acute slices from hippocampus and corpus callosum of adult mice. We show that Aqp4 deletion has a layer-specific effect on [K+]o that precisely mirrors the known effect on extracellular volume dynamics. In CA1, the peak [K+]o in stratum radiatum during 20Hz stimulation of Schaffer collateral/commissural fibers was significantly higher in Aqp4 −/− mice than in wild types, whereas no differences were observed throughout the [K+]o recovery phase. In stratum pyramidale and corpus callosum, neither peak [K+]o nor post-stimulus [K+]o recovery was affected by Aqp4 deletion. Our data suggest that AQP4 modulates [K+]o during synaptic stimulation through its effect on extracellular space volume. The Author(s), 2014 Astrocytes nationallicence AQP4 nationallicence Extracellular space nationallicence Glia nationallicence K+ homeostasis nationallicence Synaptic activation nationallicence Haj-Yasein Nadia Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut Bugge Cecilie Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut Jensen Vidar Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut Østby Ivar Centre for Integrative Genetics, Norwegian University of Life Sciences, 1432, As, Norway aut Ottersen Ole Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut Hvalby Øivind Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut Nagelhus Erlend Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut Brain Structure and Function Springer Berlin Heidelberg 220/4(2015-07-01), 2469-2474 1863-2653 220:4<2469 2015 220 429 https://doi.org/10.1007/s00429-014-0767-z text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 brief-communication jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00429-014-0767-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Haj-Yasein Nadia Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut NATIONALLICENCE 700 1- Bugge Cecilie Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut NATIONALLICENCE 700 1- Jensen Vidar Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut NATIONALLICENCE 700 1- Østby Ivar Centre for Integrative Genetics, Norwegian University of Life Sciences, 1432, As, Norway aut NATIONALLICENCE 700 1- Ottersen Ole Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut NATIONALLICENCE 700 1- Hvalby Øivind Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut NATIONALLICENCE 700 1- Nagelhus Erlend Letten Centre, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway aut NATIONALLICENCE 773 0- Brain Structure and Function Springer Berlin Heidelberg 220/4(2015-07-01), 2469-2474 1863-2653 220:4<2469 2015 220 429