%------------------------------------------------------------------------------------------ % % Title: Calcium Signals in Small Structures % Filename: CaSignal_SVREndoCalmodSphere.par % Author: Ronald van Elburg % % % Associated Paper: % Cornelisse LN, van Elburg RAJ, Meredith RM, Yuste R, Mansvelder HD (2007) % High Speed Two-Photon Imaging of Calcium Dynamics in Dendritic Spines: % Consequences for Spine Calcium Kinetics and Buffer Capacity. % PLoS ONE 2(10): e1073 doi:10.1371/journal.pone.0001073 % % % % %------------------------------------------------------------------------------------------ Structure = Sphere_Structure% Make it a sphere R_Structure = 3/Sigma % Radius of the simulated structure: Cylinder or Sphere (0.57 um) Total_Dye = 10 EndogenousBuffer.total = Total_EndogenousBuffer % Calmodulin Parameters for Dye D_Dye = 0.025 % Diffusion Constant Calmodulin pers. com. Warren Zipfel (0.025 um^2/ms) KPlus_Dye = 0.4 % Fluorescent dye calcium binding rate (0.45/(ms uM)) KD_Dye = 2 % Fluorescent dye calcium affinity (0.17 uM) path = ".\" % If running under Windows, specify here the path to the % directory containing the script imported below file = path "CaSignal_main.par" include file % Import the simulation parameters from the main script % Auxilary variables for monitoring concentrations at different distances from the membrane NoOfSteps = 6 % number of shells in the output (NOT IN THE SIMULATION, THERE THE GRIDSIZE DEFINES THE COMPARTMENTS) dR=R_Structure/NoOfSteps R1k=(NoOfSteps-0.5)*dR R6k=(NoOfSteps-5.5)*dR Ca1 := Ca[R1k] ; Dye1 := Dye[R1k] Ca6 := Ca[R6k] ; Dye6 := Dye[R6k] CaAverage:=Ca[] ; DyeAverage:=Dye[] % Exporting the variables defined above to file Exp='SVREndoCalmod' LoopVar=Sigma*100 LoopVar2=Total_EndogenousBuffer Geom='S' plot point.mute Ca1 "Output\Exp""Exp""\CSE""Exp""Geom""_Ca1_""LoopVar""_""LoopVar2" plot point.mute Ca6 "Output\Exp""Exp""\CSE""Exp""Geom""_Ca6_""LoopVar""_""LoopVar2" plot point.mute CaAverage "Output\Exp""Exp""\CSE""Exp""Geom""_CaAverage_""LoopVar""_""LoopVar2" plot point.mute Dye1 "Output\Exp""Exp""\CSE""Exp""Geom""_Dye1_""LoopVar""_""LoopVar2" plot point.mute Dye6 "Output\Exp""Exp""\CSE""Exp""Geom""_Dye6_""LoopVar""_""LoopVar2" plot point.mute DyeAverage "Output\Exp""Exp""\CSE""Exp""Geom""_DyeAverage_""LoopVar""_""LoopVar2" % Parameter variation for Total_EndogenousBuffer = 25 to 1000 step 25 for Sigma = 0.25 to 10 step 0.25 % The adaptive integration method fails for the fast calcium change % to overcome this problem we run the first 20 ms with a fixed timestep % of 0.001 ms, then after the fast changes we switch to the adaptive method % for optimal performance. Run 20.0 1.0e-3 ; current CalciumCurrent Run adaptive 480.0 1.0e-3 accuracy; current CalciumCurrent