Journal: The Journal of Neuroscience

Article Title: Distinct Roles of Kv1 and Kv3 Potassium Channels at the Calyx of Held Presynaptic Terminal

doi: 10.1523/JNEUROSCI.23-32-10445.2003

Figure Lengend Snippet: The effect of TEA and Kv1-blocking toxins on presynaptic potassium currents. A, TEA (1 mm) attenuated IPK. Left, sample records of IPK before (i, dashed lines) and after (ii, continuous lines) TEA application. Right, The I-V relationships of IPK (n = 5) before (i) and during (ii) TEA application. Inset graph shows IPK at +20 mV and -20 mV (normalized to control at each potential) at three different concentrations of TEA (logarithmic plot in abscissa). Data are derived from four cells. The current amplitude was measured at 10 msec from the onset of the command pulse (A, B, arrowheads). B, MgTX (10 nm) attenuated IPK. Left, Sample records of IPK before (i, dashed lines) and during (ii, continuous lines) MgTX application. Right, The I-V relationships of IPK (n = 4) before (i) and during (ii) MgTX application. C, DTX-I (200 nm; n = 3) (left panel) or TsTX (100 nm; n = 4) (right panel) occluded the IPK-blocking effect of MgTX. Presynaptic potassium currents before (i) and after (ii, red) application of DTX-I (left panel) or TsTX (right panel) and subsequent additions of MgTX (iii) at -20 mV are shown in the insets (superimposed) and in I-V relationships.

Article Snippet: Synthetic peptide toxins, iberiotoxin (IbTX), margatoxin (MgTX), DTX-I, and tityustoxin-Kα (TsTX) were purchased from the Peptide Institute (Osaka, Japan). fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window Figure 2. caption a7 Inward and outward currents remaining after 4-AP application.

Techniques: Blocking Assay, Control, Derivative Assay