%------------------------------------------------------------------------------------------ % % Title: Calcium Signals in Small Structures % Filename: CaSignal_Exp8HbSphere.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 % 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 % Fluorescent Dye buffer DiffusableEndogenousBuffer % Create diffusable Endogenous Buffer : Calbindin Parameters DiffusableEndogenousBuffer.D = 0.043 % diffusable Endogenous Buffer diffusion coefficient (um^2/ms) DiffusableEndogenousBuffer.total = Total_DiffusableEndogenousBuffer % Total diffusable Endogenous Buffer concentration (uM) % Binding/Unbinding Rate Constants DiffusableEndogenousBuffer.kplus = 0.09 % diffusable Endogenous Buffer calcium binding rate (1/(ms uM)) DiffusableEndogenousBuffer.KD = 0.24 % diffusable Endogenous Buffer calcium affinity (uM) % Boundary Conditions DiffusableEndogenousBuffer.bc all Neumann % No flux of diffusable Endogenous Buffer through the boundary % 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 CaBoundary:=Ca[R_Source] Ca1 := Ca[R1k] ; Dye1 := Dye[R1k] ; BndDye1 := Total_Dye-Dye[R1k] ;EndoB1 := EndogenousBuffer [R1k] Ca6 := Ca[R6k] ; Dye6 := Dye[R6k] ; BndDye6 := Total_Dye-Dye[R6k] ;EndoB6 := EndogenousBuffer [R6k] CaAverage:=Ca[] ; DyeAverage:=Dye[] ; BndDyeAverage:=Total_Dye-Dye[] ;EndoBAverage := EndogenousBuffer [] % Exporting the variables defined above to file Exp='B8Hb' LoopVar=Total_DiffusableEndogenousBuffer Geom='S' plot point.mute CaBoundary "Output\Exp""Exp""\CSE""Exp""Geom""_CaBoundary_""LoopVar" plot point.mute Ca1 "Output\Exp""Exp""\CSE""Exp""Geom""_Ca1_""LoopVar" plot point.mute Ca6 "Output\Exp""Exp""\CSE""Exp""Geom""_Ca6_""LoopVar" plot point.mute CaAverage "Output\Exp""Exp""\CSE""Exp""Geom""_CaAverage_""LoopVar" plot point.mute Dye1 "Output\Exp""Exp""\CSE""Exp""Geom""_Dye1_""LoopVar" plot point.mute Dye6 "Output\Exp""Exp""\CSE""Exp""Geom""_Dye6_""LoopVar" plot point.mute DyeAverage "Output\Exp""Exp""\CSE""Exp""Geom""_DyeAverage_""LoopVar" plot point.mute BndDye1 "Output\Exp""Exp""\CSE""Exp""Geom""_BndDye1_""LoopVar" plot point.mute BndDye6 "Output\Exp""Exp""\CSE""Exp""Geom""_BndDye6_""LoopVar" plot point.mute BndDyeAverage "Output\Exp""Exp""\CSE""Exp""Geom""_BndDyeAverage_""LoopVar" plot point.mute EndoB1 "Output\Exp""Exp""\CSE""Exp""Geom""_EndoB1_""LoopVar" plot point.mute EndoB6 "Output\Exp""Exp""\CSE""Exp""Geom""_EndoB6_""LoopVar" plot point.mute EndoBAverage "Output\Exp""Exp""\CSE""Exp""Geom""_EndoBAverage_""LoopVar" % Parameter variation for Total_DiffusableEndogenousBuffer = 0 to 200 step 40 % 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