ReadMe.txt This is the readme for the model code associated with the paper: Joshua H. Goldwyn, Nikita S. Imennov, Michael Famulare, Eric Shea-Brown. (submitted) On stochastic differential equation models for ion channel noise in Hodgkin-Huxley neurons. Submitted manuscript available at http://arxiv.org/abs/1009.4172 The following files have been uploaded to ModelDB: HH_master.f95 -- all subroutines and programs used to solve HH equations HH_run.95 -- program file for simulating HH equations (uses command line inputs, see below) Makefile -- make executable MT19937.f90 -- Mersenne twister code (written by Richard Woloshyn and downloaded from http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/VERSIONS/FORTRAN/fortran.html) NoiseData_K.txt and NoiseData_Na.txt -- data files used for noise terms in colored noise quasistationary model NonMarkov_K.mw and NonMarkov_Na.mw -- Maple files used to create NoiseData_K.txt and NoiseData_Na.txt, respectively ParameterModule.f95 -- parameter values used in HH model Usage: Create HH_run using make command Note from the ModelDB Administrator: On my Fedora Core 11 machine I found the lapack and blas library files were not found until I replaced LDFLAGS in Makefile to read LDFLAGS = -L/usr/local/epd/lib -I/usr/local/epd/include /usr/lib/liblapack.so.3 /usr/lib/libblas.so.3 Then the command line can be used: ./HH_run [Model Number] [Membrane Area] [# Time Steps] \ [Time Step Size] [# ISIs] [DC] [Noise] [Sine Amplitude] [Sine Frequency] \ [Voltage Clamp] [Data to Print Out] [Random Number Seed] output is data (format of which determined by [Data to Print Out] option, see below) Where : Model Number: 0 = ODE 1 = Markov Chain 2 = SDE Channel (Fox and Lu, 1994) 3 = SDE Subunit Identical (Fox and Lu, 1994) 4 = SDE Subunit Independent (Shuai and Jung, 2002) 5 = SDE Subunit Quasistationary 6 = Channel Quasistationary Applied Current is of the form [DC] + [Noise]*N(0,1) + [Sine Amplitude]*sin(2*Pi*[Sine Frequency]*t) Voltage Clamp: 0 = No 1 = Yes Data to Print Out: 1 = t, V, proportion of open Na channels, proportion of open K channels 2 = Interspike intervals Two specific examples of HH_run are provided in the scripts example1.sh and example2.sh that implement the following EXAMPLE 1: Run all models for a constant input (strength of DC input is 7 (micro amp / cm^2). Write out first 30 interspike intervals (in ms). EXAMPLE 2: Run all models in voltage clamp (voltage clamp to 20 mV) for 100 ms (1E4 time steps with 0.01ms step size). Write out time, voltage, proportion of open Na channels and proportion of open K channels