Fig. 2.
Comparison of transient and sustained K+ currents (Itransient and Isustained) in individual antennal lobe (AL) neurons in whole cell voltage-clamp configuration. The conductance (G) is determined by assuming EK = −98.5 mV. A: Itransient and Isustained. A1: current traces showing voltage-dependent activation of Itransient and Isustained, which were measured during the step depolarization in cells loaded with a K-gluconate patch pipette internal solution and bathed in a solution containing 10−7 M TTX and 10−3 M CdCl2. A2: current traces showing the pharmacologically isolated Itransient with additional application of 2 × 10−2 M tetraethylammonium chloride (TEA). A3: current traces showing the pharmacologically isolated Isustained with additional application of 5 × 10−3 M 4-aminopyridine (4-AP). Traces in A1, A2, and A3 were obtained from different cells. B: conductance-voltage (G-V) relationship of Itransient. C: G-V relationship of Isustained. D: comparison of absolute maximum current amplitude of Itransient. E: comparison of absolute maximum current amplitude of Isustained. F: comparison of peak current density of Itransient. G: comparison of peak current density of Isustained. *P < 0.05; n.s., not significant.