Whole-cell voltage-gated currents in isolated TRPM5-GFP-positive fungiform taste cells. In GFP-labeled cells expressing TRPM5 channels, depolarizing steps from -80 mV elicit voltage-gated inward and outward currents. The outward current is mostly blocked by TEA indicating the involvement of voltage-gated K+ channels while the inward current was blocked by TTX indicating the involvement of voltage-gated Na+ channels. Replacement of Ca2+ with Ba2+ did not reveal an inward current suggesting that these cells do not express voltage-gated Ca2+ channels. The I-V plot is represented for both inward and outward currents in Tyrodes (n = 6 cells; mean ± sem).