Figure 1.

Characteristics of the Na current (I_Na) expressed in prostate cancer cells [human prostate cancer cell line (PC-3) and Mat-LyLu rat prostate cancer cell lines]. The cells were held at −80 mV, and command voltage pulses to +0 mV were applied in PC-3 (A) and Mat-LyLu cells (B and C). (C) Effects of replacement of extracellular Na⁺ with NMDG⁺. The current traces in B and C were elicited from a holding potential of −80 mV to +0 mV. In Mat-LyLu cells, the original current traces elicited by depolarizing pulses are indicated in D. The current–voltage (I–V) relations measured at the peak are illustrated in E. The I–V relations are shown after the leakage currents were subtracted. (F) Steady-state inactivation curves for I_Na expressed in Mat-LyLu cells. The data obtained from four cells were fitted by a Bolzmann equation. NMDG, N-methyl-D-glucamine; TTX, tetrodotoxin.