Spontaneous chloride currents in poorly differentiated nasopharyngeal carcinoma cells

TLDR: A chloride channel can be activated spontaneously and occasionally under the isotonic condition in CNE-2Z cells, showing the similar characteristics to the volume-sensitive chloride channel.

Abstract: Objective To explore the spontaneous chloride currents in poorly differentiated nasopharyngeal carcinoma( CNE-2Z) cells.Methods The whole-cell patch-clamp technique was used to detect the Cl-currents.The characteristics of the currents were clarified by ATP depletion in the pipette solution,extracellular applications of chloride channel blockers and hypertonic challenges.Results A chloride current was activated spontaneously and occasionally in the isotonic solution in CNE-2Z cells,showing significant outward rectification but no time-dependent inactivation.The reversal potential of the current was(- 7.6 ± 0.9) mV,which was close to the calculated equilibrium potential for Cl-.The induction of the chloride channel was dependent on the intracellular ATP.The spontaneous chloride currents were inhibited by extracelluar applications of the chloride channel blocker ATP and 47% hypertonic solution.Conclusion A chloride channel can be activated spontaneously and occasionally under the isotonic condition in CNE-2Z cells,showing the similar characteristics to the volume-sensitive chloride channel.