in cultured glial cells from chick embryonic brain , both influx and efflux of 42k+ and 22na+ are dependent on the external ca++ and concentration ( [ ca++ ] 0 ) between 2 and 0.1 mm although intracellular concentrations of k+ ( [ k+ ] i ) and na+ ( [ na+ ] i ) do not change .
C0006104
brain
C0086045
concentrations