DOI: 10.5061/dryad.37pvmcvrw
title: The potassium channel subunit Kv1.8 (Kcna10) is essential for the distinctive outwardly rectifying conductances of type I and II vestibular hair cells

description: In amniotes, head motions and tilt are detected by two types of vestibular
 hair cells (HCs) with strikingly different morphology and physiology.
 Mature type I HCs express a large and very unusual potassium conductance,
 gK,L, which activates negative to resting potential, confers very negative
 resting potentials and low input resistances and enhances an unusual
 non-quantal transmission from type I cells onto their calyceal afferent
 terminals. Following clues pointing to KV1.8 (Kcna10) in the Shaker K
 channel family as a candidate gK,L subunit, we compared whole-cell
 voltage-dependent currents from utricular hair cells of KV1.8-null mice
 and littermate controls. We found that KV1.8 is necessary not just for
 gK,L but also for fast-inactivating and delayed rectifier currents in type
 II HCs, which activate positive to resting potential. The distinct
 properties of the three KV1.8-dependent conductances may reflect different
 mixing with other KV subunits that are reported to be differentially
 expressed in type I and II HCs. In KV1.8-null HCs of both types, residual
 outwardly rectifying conductances include KV7 (KCNQ) channels. Current
 clamp records show that in both HC types, KV1.8-dependent conductances
 increase the speed and damping of voltage responses. Features that speed
 up vestibular receptor potentials and non-quantal afferent transmission
 may have helped stabilize locomotion as tetrapods moved from water to
 land.
description: We compared whole-cell voltage-activated K<sup>+
 </sup>currents in type I and type II hair cells from homozygous
 knockout
 (<em>Kcna10</em><sup>–</sup><sup>/</sup><sup>–</sup>) animals and their wildtype (<em>Kcna10</em><sup>+/+</sup>) or heterozygote (<em>Kcna10</em><sup>+/–</sup>) littermates. We immunolocalized K<sub>V</sub>1.8 subunits in the utricular epithelium and pharmacologically characterized the residual K<sup>+</sup> currents of <em>Kcna10</em><sup>–/–</sup> animals. We performed current-clamp experiments to assess the impact of K<sub>V</sub>1.8-dependent currents on passive membrane properties.
description: # The potassium channel subunit KV1.8 (Kcna10) is essential for the
 distinctive outwardly rectifying conductances of type I and II vestibular
 hair cells --- This README file was generated on 2023-10-06 by Hannah R.
 Martin. It can be read with Markdown syntax. These datasets contain
 processed data used in the analyses of patch clamp electrophysiology in
 semi-intact utricles from mice. The study investigates the role of Kv1.8
 conductances in vestibular hair cells. Datasets are in Excel or CSV
 format. Datasets have headers, and additional information is provided in
 this document. ## Version change log **02-oct-2024:** Renamed files to
 reflect minor changes in figure organization during the review process so
 that readers of the associated manuscript can find the correct
 spreadsheet. 1. SF1_sourcedata renamed to F1-fs1_sourcedata 2.
 SF2_sourcedata renamed to F2-fs1_sourcedata 3. SF3_sourcedata renamed to
 F2-fs2_sourcedata 4. SF4_sourcedata renamed to F2-fs3_sourcedata 5.
 SF5_sourcedata renamed to F7-fs1_sourcedata 6. SF6_sourcedata renamed to
 F7-fs2_sourcedata ## GENERAL INFORMATION 1. Author Information A.
 Principal Investigator Contact Information Name: Ruth Anne Eatock
 Institution: The University of Chicago Address: Chicago, IL USA Email:
 [eatock@uchicago.edu](mailto:eatock@uchicago.edu) B. First Author Contact
 Information Name: Hannah R. Martin Institution: The University of Chicago
 Address: Chicago, IL USA Institutional Email:
 [hrmartin@uchicago.edu](mailto:hrmartin@uchicago.edu) Permanent Email:
 [hannahrsmartin@gmail.com](mailto:hannahrsmartin@gmail.com) 2. Date of
 data collection: 2017-2023 ## SHARING/ACCESS INFORMATION Blank cells: Any
 blank cells in the Excel/CSV files indicate a lack of data for that
 variable and observation. ## DATA & FILE OVERVIEW 1. Each file
 corresponds to a figure in the manuscript and contains sufficient data to
 recreate all statistical tests. Each .xlsx file contains sheets that are
 explicitly labelled to refer to a panel within that figure. Each sheet has
 unambiguous header information describing the parameter (details on
 analysis methods are found in the Methods section of the manuscript),
 condition (genotype, age, zone, drug), and the unique CellID of every cell
 used in the analysis. * Voltage-Clamp Data *F1_sourcedata.xlsx*
 *F3_sourcedata.xlsx* *F6_sourcedata.xlsx* *F1-fs1_sourcedata.xlsx*
 *F3-fs1_sourcedata.xlsx* *F3-fs2_sourcedata.xlsx* *F3-fs3_sourcedata.xlsx*
 *F7-fs1_sourcedata.xlsx* *F7-fs2_sourcedata.xlsx* * Current-Clamp Data
 *F2_sourcedata.xlsx* *F4_sourcedata.xlsx* * Pharmacology Data
 *F7_sourcedata.xlsx* 2. Relationship between files: Some data is repeated
 in different files if it is used in multiple figures. This is easily seen
 if when the unique CellID for each data entry is found in multiple files.
 Below are the files that share some data between them: * F1_sourcedata,
 F1-fs1_sourcedata: F1-fs1_sourcedata shows data from a wider age range
 than F1_sourcedata * F3_sourcedata, F3-fs1_sourcedata, F3-fs2_sourcedata:
 F3-fs1_sourcedata contains the individual data points that are represented
 by mean and SEM in F3_sourcedata; F3-fs2_sourcedata shows data from a
 wider age range than F3-fs1_sourcedata 3. Additional related data
 collected that was not included in the current data package:
 Immunohistochemistry data was included because it was not used
 quantitatively. #### DATA-SPECIFIC INFORMATION Additional information for
 some sheets within files is provided below. ##### Voltage-Clamp Data
 *Filename: F1_sourcedata.xlsx* Sheet name: **F1C** Number of Variables: 12
 1. V_het: mV, step voltage of the representative Kv1.8+/- type I HC 2.
 G_het: nS, tail conductance of the representative Kv1.8+/- type I HC 3.
 Gnorm_het: normalized tail conductance of the representative Kv1.8+/- type
 I HC 4. V_ko: mV, step voltage of the representative Kv1.8-/- type I HC 5.
 G_ko: nS, tail conductance of the representative Kv1.8-/- type I HC 6.
 Gnorm_ko: normalized tail conductance of the representative Kv1.8-/- type
 I HC 7. V_het_fit: mV, voltages of Boltzmann fit of representative
 Kv1.8+/- type I HC 8. G_het_fit: nS, fit conductance values of the
 representative Kv1.8+/- type I HC 9. Gnorm_het_fit: normalized fit
 conductance of the representative Kv1.8+/- type I HC 10. V_ko_fit: mV,
 voltages of Boltzmann fit of representative Kv1.8-/- type I HC 11
 G_ko_fit: nS, fit conductance values of the representative Kv1.8-/- type I
 HC 11. Gnorm_ko_fit: normalized fit conductance of the representative
 Kv1.8-/- type I HC Sheet name: **F1D** Number of variables: 16 1. CellID:
 Unique cell identifier 2. Genotype: Kcna10-TM45 3. Age: Postnatal Days 4.
 Weight: Grams. Blank means the weight was not recorded. 5. Sex: Male or
 Female. Blank means the sex was not determined. 6. Zone: Zone location
 within the utricle 7. Vhalf: in mV, the midpoint of activation of the tail
 G-V curve 8. S: in mV, the slope factor of the tail G-V curve 9. gmin: in
 nS, the minimum of the tail G-V curve 10. gmax: in nS, the maximum of the
 tail G-V curve 11. Cm: in pF, the capacitance of the cell measured in HEKA
 12. Gdensity: in nS/pF, (gmax - gmin)/Cm 13. Rs: in megaOhms, the series
 resistance 14. Rs_comp: in percent, the percent compensation of series
 resistance 15. VCfile1: the name of the best quality voltage-clamp file
 used for these parameters 16. VCfile2: the name of the second-best quality
 voltage-clamp file *Filename: F3_sourcedata.xlsx* Sheet name: **F3A**
 Number of variables: 15 Variable List: 1. Time: ms 2. I_WT_LES: current
 normalized by max 3. I_WT_LES_fit: current fit to Equation 4, normalized
 to max 4. I_WT_MES: current normalized by max 5. I_WT_MES_fit: current fit
 to Equation 4, normalized to max 6. I_WT_Striola: current normalized by
 max 7. I_WT_Striola_fit: current fit to Equation 4, normalized to max 8.
 Genotype: KCNA10-TM45 9. Zone: utricular location 10.
 Tau_FastInactivation_Mean_ms: ms, mean fast time constant of inactivation
 11. Tau_FastInactivation_SEM: ms, standard error of the mean 12.
 Tau_FastInactivation_N: number of cells 13.
 Fraction_FastInactivation_Mean: mean relative amplitude of fast
 inactivation to total inactivation 14. Fraction_FastInactivation_SEM:
 standard error of the mean 15. Fraction_FastInactivation_N: number of
 cells Sheet name: **F3C** Number of Variables: 5 1. Genotype: KCNA10-TM45
 2. Zone: utricular location 3. PercentInactivation_Mean: %, inactivating
 current as a percent of total current 4. PercentInactivation_SEM: standard
 error of the mean 5. PercentInactivation_N: number of cells Sheet name:
 **F3D** Number of variables: 43 Variable List: For panel Fig 3D1 1. Time:
 ms 2. I_WT_LES: nA, representative current response from Kv1.8+/+ LES type
 II HC 3. I_WT_LES_fit: nA, fit curve 4. I_HET_LES: nA, representative
 current response from Kv1.8+/- LES type II HC 5. I_HET_LES_fit: nA, fit
 curve 6. I_KO_LES: nA, representative current response from Kv1.8-/- LES
 type II HC 7. I_KO_LES_fit: nA, fit curve 8. VpkMean_WT: mV, mean of step
 voltages of Kv1.8+/+ LES type II HCs 9. GpkMean_WT: nS, mean of peak
 conductances of Kv1.8+/+ LES type II HCs 10. GpkSEM_WT: nS, SEM of peak
 conductances of Kv1.8+/+ LES type II HCs 11. Npk_WT: number of Kv1.8+/+
 LES type II HCs 12. GpkMeanNorm_WT: peak conductances of Kv1.8+/+ LES type
 II HCs, normalized by Gmax 13. GpkSEMNorm_WT: SEM of peak conductances of
 Kv1.8+/+ LES type II HCs, normalized by Gmax 14. VpkFit_WT: mV, voltage of
 fit curve to mean peak conductance 15. GpkFit_WT: nS, conductance of fit
 curve to mean peak conductance 16. GpkFitNorm_WT: conductance of fit curve
 to mean peak conductance, normalized by Gmax 17. VssMean_WT: mV, mean of
 step voltages of Kv1.8+/+ LES type II HCs 18. GssMean_WT: nS, mean of
 steady-state conductances of Kv1.8+/+ LES type II HCs 19. GssSEM_WT: nS,
 SEM of steady-state conductances of Kv1.8+/+ LES type II HCs 20. Nss_WT:
 number of Kv1.8+/+ LES type II HCs 21. GssMeanNorm_WT: steady-state
 conductances of Kv1.8+/+ LES type II HCs, normalized by Gmax 22.
 GssSEMNorm_WT: SEM of steady-state conductances of Kv1.8+/+ LES type II
 HCs, normalized by Gmax 23. VssFit_WT: mV, voltage of fit curve to mean
 steady-state conductance 24. GssFit_WT: nS, conductance of fit curve to
 mean steady-state conductance 25. GssFitNorm_WT: conductance of fit curve
 to mean steady-state conductance, normalized by Gmax 26. VpkMean_KO: mV,
 mean of step voltages of Kv1.8-/- LES type II HCs 27. GpkMean_KO: nS, mean
 of peak conductances of Kv1.8+-/- LES type II HCs 28. GpkSEM_KO: nS, SEM
 of peak conductances of Kv1.8-/- LES type II HCs 29. Npk_KO: number of
 Kv1.8-/- LES type II HCs 30. GpkMeanNorm_KO: peak conductances of Kv1.8-/-
 LES type II HCs, normalized by Gmax 31. GpkSEMNorm_KO: SEM of peak
 conductances of Kv1.8-/- LES type II HCs, normalized by Gmax 32.
 VpkFit_KO: mV, voltage of fit curve to mean peak conductance 33.
 GpkFit_KO: nS, conductance of fit curve to mean peak conductance 34.
 GpkFitNorm_KO: conductance of fit curve to mean peak conductance,
 normalized by Gmax 35. VssMean_KO: mV, mean of step voltages of Kv1.8-/-
 LES type II HCs 36. GssMean_KO: nS, mean of steady-state conductances of
 Kv1.8-/- LES type II HCs 37. GssSEM_KO: nS, SEM of steady-state
 conductances of Kv1.8-/- LES type II HCs 38. Nss_KO: number of Kv1.8-/-
 LES type II HCs 39. GssMeanNorm_KO: steady-state conductances of Kv1.8-/-
 LES type II HCs, normalized by Gmax 40. GssSEMNorm_KO: SEM of steady-state
 conductances of Kv1.8-/- LES type II HCs, normalized by Gmax 41.
 VssFit_KO: mV, voltage of fit curve to mean steady-state conductance 42.
 GssFit_KO: nS, conductance of fit curve to mean steady-state conductance
 43. GssFitNorm_KO: conductance of fit curve to mean steady-state
 conductance, normalized by Gmax *Filename: F6_sourcedata.xlsx* Sheet name:
 **F6B** Number of Variables: 12 1. Vpeak: mV, for the x-axis of the
 representative activation curve in the h-infinity plot 2. Gpeak: nS, for
 y-axis 3. Gpeak_norm: Gpeak/Gmax 4. Vpeakfit: mV, x-values for fit curves
 5. Gpeakfit: nS 6. Gpeak_normfit 7. Vinac: mV, for the x-axis of the
 representative inactivation curve in the h-infinity plot 8. Ginac: nS 9.
 Ginac_norm: Ginac/Gmax 10. Vinacfit: mV 11. Ginacfit: nS 12. Ginax_normfit
 *Filename: F1-fs1_sourcedata.xlsx* Sheet name: **A** Number of Variables:
 14 Variable List: 1. CellID: Unique cell identifier 2. Genotype:
 KCNA10-TM45 genotype 3. Age: postnatal day 4. Weight: grams 5. Sex 6.
 Zone: Utricular zone 7. Vhalf: mV, tail Vhalf 8. S: mV, tail slope factor
 9. gmin: nS, tail Gmin 10. gmax: nS, tail Gmax 11. Cm: pF, cell
 capacitance 12: Gdensity: nS/pF, (gmax - gmin)/Cm 12. VCfile1: best
 voltage clamp file name 14: VCfile2: second best voltage clamp file name
 Sheet name: **B** Number of Variables: 8 Variable List: 1. CellID: unique
 cell identifier 2. Genotype: KCNA10-TM45 genotype 3. Age: postnatal day 4.
 Zone: Utricular zone 5. Vhalf: mV, tail Vhalf 6. Gdensity: nS/pF, (gmax -
 gmin)/Cm 7. Group: see Variable 8 8. GroupName: informative name that
 describes which group the cells are in (age range, with or without gKL,
 without or without Kv1.8) *Filename: F3-fs1_sourcedata.xlsx* Sheet name:
 **Sheet1** Number of variables: 15 Variable List: 1. CellID: Unique cell
 identifier 2. Genotype: KCNA10-TM45 genotype 3. Age: Postnatal Days 4.
 Weight: Grams. Blank means the weight was not recorded. 5. Sex: Male or
 Female. Blank means the sex was not determined. 6. Zone: Zone location
 within the utricle 7. Cm: in pF, the capacitance of the cell measured in
 HEKA 8. PercentInactivation: %, percent inactivation at 30 mV 9.
 tau_Activation: ms, from fit to Eq. 3 or Eq. 4 10. tau_FastInactivation:
 ms, from fit to Eq. 4 11. Inactivation_FastFraction: from fit to Eq. 4 12.
 Rs: in megaOhms, the series resistance 13. Rs_comp: in percent, the
 percent compensation of series resistance 14. VCfile1: the name of the
 best quality voltage-clamp file used for these parameters 15. VCfile2: the
 name of the second-best quality voltage-clamp file *Filename:
 F3-fs2_sourcedata.xlsx* Sheet name: **Sheet1** Number of variables: 21
 Variable List: 1. CellID: Unique cell identifier 2. Genotype: KCNA10-TM45
 genotype 3. Age: Postnatal Days 4. Weight: Grams. Blank means the weight
 was not recorded. 5. Sex: Male or Female. Blank means the sex was not
 determined. 6. Zone: Zone location within the utricle 7. Cm: in pF, the
 capacitance of the cell measured in HEKA 8. peak_Vhalf: mV, midpoint of
 activation of peak conductance voltage curve 9. peak_S: mV, slope factor
 of peak conductance-voltage fit 10. peak_Gmax: nS, gmax of peak
 conductance-voltage fit 11. peakGdensity: nS/pF, gmax/Cm 12. ss_Vhalf: mV
 13. ss_S: mV 14. ss_Gmax: nS 15. ss_Gdensity: nS/pF 16. inac_Gdensity:
 nS/pF 17. PercentInactivation: % 18. Rs: megaOhm, total series resistance
 19. Comp: %, percent compensation of series resistance 20. VCfile1: the
 name of the best quality voltage-clamp file used for these parameters 21.
 VCfile2: the name of the second-best quality voltage-clamp file *Filename:
 F3-fs3_sourcedata.xlsx* Sheet name: **A** Number of variables: 3 1.
 IA30WT: %, percent inactivation in Kv1.8+/+ type II HCs &gt;P12 2.
 IA30HET: %, percent inactivation in Kv1.8+/- type II HCs &gt;P12 3.
 IA30KO: %, percent inactivation in Kv1.8-/- type II HCs &gt;P12 Sheet
 name: **B** Number of variables: 20 1. Time: ms 2. I_fit: nA, fit curve of
 double exponential decay fit to current at 30 mV 3. CellID: unique cell
 identifier 4. Genotype: KCNA10-TM45 5. Age: Postnatal day 6. Weight: g 7.
 Sex 8. Zone: Utricular location 9. Cm: pF, cell capacitance 10. peakVhalf:
 mV, the midpoint of activation of peak conductance voltage curve 11.
 peakS: mV, slope factor of peak conductance-voltage fit 12. peakGdensity:
 nS/pF, gmax/Cm 13. ssVhalf: mV 14. ssS: mV 15. ssGDensity: nS/pF 16.
 inacGdensity: nS/pF 17. PercentInactivation: % 18. tau_activatiom: ms 19.
 tau_inactivationFast: mS 20. fastFraction: amplitude of fast inactivation
 relative to total inactivation *Filename: F7-fs1_sourcedata.xlsx* Sheet
 name: **A** Number of variables: 2 1. Time: ms 2. I_fit: nA, exponential
 decay fit of representative XE991-sensitive current in Kv1.8-/- type I HC
 from the striola Sheet name: **B** Number of variables: 4 1. Vtail: mV 2.
 Gtail: nS, representative XE991-sensitive tail conductance in Kv1.8-/-
 type I HC from the striola 3. Vtail_fit: mV 4. Gtail_fit: nS, from double
 Boltzmann fit Sheet name: **C** Number of variables: 2 1.
 KO_ES_TypeI_tailVhalf: tail Vhalf values of Kv1.8-/- type I HCs (&gt;P12)
 from the extrastriola 2. KO_Striola_TypeI_tailVhalf: tail Vhalf values
 (including single and double Boltzmann fits) of Kv1.8-/- type I HCs
 (&gt;P12) from the striola *Filename: F7-fs2_sourcedata.xlsx* Sheet name:
 **A** Number of variables: 12 Variable List: 1. Time: ms 2. WH_TypeI_ES:
 nA, representative Kv1.8+/+,+/- type I HC from the extrastriola 3.
 WH_TypeI_Striola: nA, representative Kv1.8+/+,+/- type I HC from the
 striola 4. KO_TypeI_ES: nA, representative Kv1.8-/- type I HC from the
 extrastriola 5. KO_TypeI_Striola1: nA, first representative Kv1.8-/- type
 I HC from the striola 6. KO_TypeI_Striola2: nA, second representative
 Kv1.8-/- type I HC from the striola 7. KO_TypeI_Striola3: nA, third
 representative Kv1.8-/- type I HC from the striola 8. WH_TypeII_ES: nA,
 representative Kv1.8+/+,+/- type II HC from the extrastriola 9.
 WH_TypeII_Striola: nA, representative Kv1.8+/+,+/- type II HC from the
 striola 10. KO_TypeII_ES: nA, representative Kv1.8-/- type II HC from the
 extrastriola 11. KO_TypeII_Striola: nA, representative Kv1.8-/- type II HC
 from the striola 12. V: mV, voltage waveform for representative currents
 Sheet name: **B** 1. CellID: Unique cell identifier 2. HCType: Type I or
 II 3. Genotype: KCNA10-TM45 genotype 4. Age: Postnatal Day 5. Zone:
 utricular 6. Cm: pF, cell size 7. IHandIKirDensity: -1*pA/pF #####
 Current-Clamp Data *Filename: F2_sourcedata.xlsx* Sheet name: **F2A**
 Number of variables: 12 Variable List: 1. CellID: Unique cell identifier
 2. Genotype: KCNA10-TM45 genotype 3. Age: Postnatal Days 4. Weight: Grams.
 Blank means the weight was not recorded. 5. Sex: Male or Female. Blank
 means the sex was not determined. 6. Zone: Zone location within the
 utricle 7. Cm: pF, the capacitance of the cell measured in HEKA 8. Vm: mV,
 the resting membrane potential at 0 pA current injection 9. Rm: megaOhms,
 the input resistance is the ratio of steady-state voltage to injected
 current 10. cTauRC: ms, the membrane time constant is the product of Cm
 and Rm 11. CCfile1: best quality current-clamp file used for these
 parameters 12. CCfile2: second-best quality current-clamp file Sheet name:
 **F2B3** Number of variables: 4 Variable List: 1. Time: ms 2. Vnorm_het:
 voltage response of representative Kv1.8+/- type I HC normalized by peak
 response 3. Vnorm_KO: voltage response of representative Kv1.8-/- type I
 HC normalized by peak response 4. I_inj: step of injected current,
 normalized by current amplitude *Filename: F4_sourcedata.xlsx* Sheet name:
 **F4AE** Number of variables: 12 Variable List: 1. CellID: Unique cell
 identifier 2. Genotype: KCNA10-TM45 genotype 3. Age: Postnatal Days 4.
 Zone: Zone location within the utricle 5. Cm: pF, the capacitance of the
 cell measured in HEKA 6. Vrest: mV, the resting membrane potential at 0 pA
 current injection 7: I_inj: pA, the small step used to fit with an
 exponential growth equation 8: deltaV: mV, a fit parameter, the amplitude
 of the voltage response 7. tau: ms, time constant of fit to exponential
 growth function 8. V0: mV, baseline of fit 9. R2: R-squared value of fit
 10. FitEndTime: user-selected time to stop the fit 11. Rinput: GigaOhms,
 deltaV divided by I_inj 12. peakTime: ms, delay of the peak of the
 depolarizing transient upon 170 pA current injection 13. peakHeight: mV,
 absolute height of the depolarizing transient upon 170 pA current
 injection Sheet name: **F4C2** Number of variables: 8 Variable List: 1.
 CellID: Unique cell identifier 2. Zone: Location within the utricle 3.
 Genotype: KCNA10-TM45 genotype 4. Age: Postnatal Days 5. I_Inj: pA,
 magnitude of current injection 6. f: Hz, frequency of resonance from fit
 to Equation 5 7. Q: Quality factor from Equation 6 8. R2: R-squared value
 of fit to Equation 5 Sheet name: **F4D** Number of variables: 4 1. Time:
 ms 2. Vnorm_HET: voltage response in Kv1.8+/- type II HC, normalized by
 peak 3. Vnorm_KO: voltage response in Kv1.8-/- type II HC, normalized by
 peak 4. Inorm_inj: current step waveform, normalized by step amplitude
 ##### Pharmacology with XE991 *Filename: F7_sourcedata* Sheet name:
 **F7B** Number of variables: 10\ Variable List: 1. CellID: Unique cell ID
 2. Zone: Utricular zone 3. Age: Postnatal day 4. Genotype: KCNA10-TM45 5.
 Weight: in grams, the weight of the mouse 6. Sex: Male or Female 7.
 HCType: Type I or II HCCm: in pF, cell capacitance 8.
 XE991_sensitive_Vhalf: in mV, the midpoint voltage of activation of the
 difference current tail G-V curve (current in 0 uM XE991 - current in 10
 uM XE991) 9. XE991_sensitive_gDensity: in nS/pF, the (gmax - gmin)/Cm of
 the difference current tail G-V curve 10. PercentBlock: in percent,
 percent that the gDensity was of the total before the drug Sheet name:
 **F7B_GV** Number of variables: 9 1. V_KOTypeI: mV, step voltage of
 Kv1.8-/- type I HC 2. Gfit_mean_KOTypeI: nS, mean Boltzmann fits to
 XE991-sensitive tail conductances of Kv1.8-/- type I HCs 3.
 Gfit_sem_KOTypeI: nS, sem of Boltzmann fits to XE991-sensitive tail
 conductances of Kv1.8-/- type I HCs 4. V_KOTypeII: mV, step voltage of
 Kv1.8-/- type II HC 5. Gfit_mean_KOTypeII: nS, mean Boltzmann fits to
 XE991-sensitive tail conductances of Kv1.8-/- type II HCs 6.
 Gfit_sem_KOTypeII: nS, sem of Boltzmann fits to XE991-sensitive tail
 conductances of Kv1.8-/- type II HCs 7. V_WTTypeII: mV, step voltage of
 Kv1.8+/+ type II HC 8. Gfit_mean_WTTypeII: nS, mean Boltzmann fits to
 XE991-sensitive tail conductances of Kv1.8+/+ type II HCs 9.
 Gfit_sem_WTTypeII: nS, sem of Boltzmann fits to XE991-sensitive tail
 conductances of Kv1.8+/+ type II HCs