Potassium channel expression level is dependent on the proliferation state in the GH3 pituitary cell line.

Previously, we showed that the peak density of the transient outward K(+) current (I(to)) expressed in GH3 cells was different in the S phase than in other phases of the cell cycle. Using cell synchronization, we show here that I(to) drops precisely at the quiescent (G(0) phase)/proliferating transition. This change is not due to a modification in the voltage dependence of I(to), but rather to a modification in its inactivation kinetics.