NEURON Tutorial #11

Goals: Examine activation and deactivation kinetics of Ih.

Specific Aims:

Add voltage clamp experiment.
Fit current traces and get tau.
Compare tau in different situations.
Examined situations: s, (1 - s), s², (1 - s)², 1 - s²

Downloads:

_Main.hoc - Program start here
ExperimentControl.hoc - Experiment contols
ParameterControl.hoc - Parameter controls
RunControl.hoc - Run controls
Fitting.hoc - Procedures for fitting
GraphVI.hoc - Voltage and current plot
1_Pulse.hoc - For pulse experiment (membrane time connstant)
2_Step.hoc - For step experiment (Rin, sag, rebound slope)
3_Alpha.hoc - For alpha experiment ( alpha summation)
4_Chirp.hoc - For chirp experiment
5_VoltageClamp.hoc - Voltage clamp experiment
11.zip - Comprises all files.

Order

Comparison:
s² shifts the curve to the left.
(1 - s²) shifts the curve to the right.

s (control)	s²	1 - s²
gbar_h = 5.3e-5 (S/cm2) vhalf = -80.5 (mV) k = 6.7 (mV)	gbar_h = 6.7e-5 (S/cm2) vhalf = -73.05 (mV) k = 7.97 (mV)	gbar_h = 4.6e-5 (S/cm2) vhalf = -87.95 (mV) k = -7.97 (mV)
Tau = 24.34 (ms) Rin = 44.51 (MΩ) Sag = 21.47 (%) Temporal Summation = 7.31 (%) Depolarizing Resonance Frequency = 4.2 (Hz) Hyperpolarizing Resonance Frequency = 4.8 (Hz)	Tau = 24.30 (ms) Rin = 38.37 (MΩ) Sag = 28.64 (%) Temporal Summation = 1.61 (%) Depolarizing Resonance Frequency = 4.9 (Hz) Hyperpolarizing Resonance Frequency = 5.4 (Hz)	Tau = 24.41 (ms) Rin = 48.03 (MΩ) Sag = 18.35 (%) Temporal Summation = 10.13 (%) Depolarizing Resonance Frequency = 3.7 (Hz) Hyperpolarizing Resonance Frequency = 4.5 (Hz)

Activation Tau

Activation

Deactivation Tau

Deactivation Tau

The results of time constants are not satisfactory.