Hypertonicity enhances expression of functional Na+/K+/2Cl- cotransporters in Ehrlich ascites tumour cells

Ehrlich cells exposed to a hypertonic medium for five hours respond by an increased expression of Na+/K+/2Cl- cotransport proteins as estimated from immunoprecipitations using polyclonal anti-cotransporter antibodies. The 3.4-fold increase in cotransport expression is followed by a concomitant 2.6-fold increase in the maximal bumetanide-sensitive K+ influx during regulatory volume increase, indicating a 2.6-fold increase in the number of functional cotransporters in the plasma membrane.