The basophilic leucaemia cells (RBL) exhibit an inwardly rectifying potassium current, IKIR. Besides this, there is also a small outward current component flowing through these channels. Changing the external K+ concentration leads to a change of the current amplitude of the inward current and thus, is a good way to study the speed of the external solution exchange. |
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Current response in RBL cells. Traces were recorded at -100 mV in the presence of low and high external K+ concentration. Low K+ (4.5 mM K+), high K+ (143 mM K+). Exchange times for external solutions are <100 ms. |