Figure 12.

Steady state KCC flux (•) and inverse lag time for inactivation (○) at 37°C after preactivation of KCC in 207 mosmol/kg medium for 15 min at 37°C. After preactivation, cells were centrifuged and maintained at 37°C before resuspending at 37°C in ⁸⁶Rb-containing media (5 mM K⁺) of osmolality 207, 248, 279, 309, or 341 mosmol/kg. In all but the 207 mosmol/kg medium, the flux inactivated soon after the cells were suspended in the new medium, and the lag time for inactivation was calculated from the influx data. A separate inactivation experiment at 37°C gave indistinguishable results.