This simulation was used in the following article: Neymotin SA, McDougal RA, Sherif MA, Fall CP, Hines ML, Lytton WW. Neuronal calcium wave propagation varies with changes in endoplasmic reticulum parameters: a computer model. Neural Computation 2015 (in press). The code in this folder generates Fig. 2 (basic calcium wave) and Fig. 11 (varying AMPA synapse stimulation parameters and view effects on the calcium wave). The simulations were tested/developed on LINUX systems, but may run on Microsoft Windows or Mac OS. To run the demo, you will need the NEURON simulator (available at http://www.neuron.yale.edu) compiled with python enabled. To draw the output you will need to have Matplotlib installed ( http://matplotlib.org/ ). Instructions to run the model - unzip the file - cd ca1dDemo - nrnivmodl (compiles the NMODL files) The nrnivmodl command will produce an architecture-dependent folder with a script called special. On 64 bit systems the folder is x86_64. Note that these simulations will run with NEURON's variable time step activated, in order to reduce the time it takes to run the simulation. However, the simulation can still take a long time to run, depending on your hardware setup. Therefore, the code is setup to save simulation data to a folder called /data within the simulation directory. ---------------------------------------------------------------------- Running and plotting the baseline calcium wave figure (Fig. 2): # run the following code in a terminal from within the directory containing the model files: python from batch import * baseRun() # run and save a file of numpy arrays baseDraw() # should show a plot of fig. 2 in the article The figure shows Ca2+ wave propagation with baseline parameters. Elevated IP3 stimulus placed at mid-dendrite (500 um on y-axis) after 2 s past start of simulation. The plot on the left depicts cytosolic [Ca2+] showing a wave of increased concentration. The plot on the right of ER [Ca2+ ] shows a mirror image wave of decreased concentration as Ca2+ is released to cytosol. ---------------------------------------------------------------------- Running and plotting Fig. 11 (electrochemical model which shows effect of AMPA receptor stimulation on release of calcium from ER): # you will be running 2 simulations with 2 different configuration files (one for no AMPA receptor stimulation and one for stimulation of AMPA receptor with 150 inputs). Both configuration files insert a set of ion channels in the dendritic section. # this first simulation takes less time to run (~75 seconds on a Xeon E5/Core i7 Integrated Memory Controller processor): python -i cawave.py AMPA0.cfg # the following simulation took ~54 minutes when run using the same processor: python -i cawave.py AMPA150.cfg To plot the output from these simulations, run the following (after you exit from the previous simulations): python from batch import * execfile('plot_fig11.py') The figure shows electrical stimulation with increased number of AMPA activations enhancing Ca2+ waves induced by IP3 (2.5 mM at 7 s). The left column shows control simulation: Ca2+ wave with no AMPA inputs prior to the IP3 stimulus. Middle column shows Ca2+ wave with train of 150 AMPA inputs (onset: 3 s; interspike interval: 25 ms) prior to the IP3 stimulus. The column on the right is a comparison of voltage (top), ER Ca2+ (middle), and cytosolic Ca2+ (bottom) in control (black) and simulation with 150 AMPA inputs (red). NOTE: If you are interested in running the simulation for a shorter period of time, you can modify the configuration files AMPA0.cfg and AMPA150.cfg. Change the value of tstop under [run] to the time you're interested in (in milliseconds). However, the resulting figure will not be identical to Fig. 11 in the publication. ---------------------------------------------------------------------- For questions/comments email: mohamed dot sherif dot md at gmail dot com or samn at neurosim dot downstate dot edu or robert dot mcdougal at yale dot edu Changelog --------- 20160915 This updated version from the Lytton lab allows their models which contain misc.mod and misc.h to compile on the mac. 20220523 Updated MOD files to contain valid C++ and be compatible with the upcoming versions 8.2 and 9.0 of NEURON.