// PARAMETER FILE FOR NEURON 'block' : mitral cell model under // conditions of TEA and TTX block // Author : Upi Bhalla // Mar 29 1991 // Highly detailed model of mit cell with experimental averages for // cell geometry. // Format of file : // x,y,z,dia are in microns, all other units are SI (Meter Kilogram Second Amp) // In polar mode 'r' is in microns, theta and phi in degrees // Control line options start with a '*' // The format for each compartment parameter line is : //name parent r theta phi d ch dens ... //in polar mode, and in cartesian mode : //name parent x y z d ch dens ... // Coordinate mode *cartesian *relative // Specifying constants *set_global EREST_ACT -0.065 ///// Aditya translated Davison's Bhalla and Bower adapted 7 compartment model from Neuron into Genesis. ///// Davison's model has pseudo compartments interleaved within proper compartments soma, prim, glom and dend. ///// pseudo compartments have only Ra and negligible Cm and Rm. // #print self.Rs2d # 5154639 Ohms // #print self.Rs2p # 18281535.6 Ohms // #print self.Rp2g # 17064846 Ohms // Ra = RA l / (pi r^2) = RA / (pi r^2), Rm = RM / (2 pi r l), Cm = CM * (2 pi r l) ///// proper compartments have only Rm and Cm, negligible Ra. ///// But cannot set Ra, Rm, Cm values to less than 1e-15, hence CM = 1e-3. However, 1e-15 leads to numerical error accumulation so set reasonable values ///// This is done to ensure no difference between symmetric and asymmetric compartments. *set_global RA 1e-4 *set_global CM 0.01 *set_global RM 10 //soma none 100 0 0 16 LCa3_mit_usb 40 K_mit_usb 28 KA_bsg_yka 58.7 Ca_mit_conc 5.2e-6 Kca_mit_usb 142 Na_mit_usb 1532 K2_mit_usb 1956 //LCa3_mit_usb causes a 15ms current transient with voltage clamp in mitral cell (Ca ionic channels might cause part of observed 'IPSC'.) - fig 2A left of Isaacson & Westbrook 1998. //To remove double spikes, the fast first one of which does not propagate into the soma, can increase KA to 587 or LCa3 to 400. soma none 100 0 0 16 LCa3_mit_usb 40 K_mit_usb 28 KA_bsg_yka 58.7 Ca_mit_conc 5.2e-6 Kca_mit_usb 142 Na_mit_usb 1532 K2_mit_usb 1956 *set_global RM 1e5 *set_global CM 1e-3 // set such that Rs2p # 18281535.6 Ohms *set_global RA 57.433089 s2p soma 1 0 0 2 *set_global RA 1e-4 *set_global CM 0.01 *set_global RM 10 //prim s2p 100 0 0 104 LCa3_mit_usb 22 K_mit_usb 17.4 K2_mit_usb 12.3 Na_mit_usb 13.4 // fast and full propagation along primary dendrite: prim s2p 100 0 0 104 LCa3_mit_usb 10 K_mit_usb 17.4 K2_mit_usb 123 Na_mit_usb 134 *set_global RM 1e5 *set_global CM 1e-3 // set such that Rs2p # 17064846 Ohms *set_global RA 53.6107495 p2g prim 1 0 0 2 *set_global RA 1e-4 *set_global CM 0.01 *set_global RM 10 // original bhalla and bower model had K_mit_usb as 28, but Davison used 200 as he says glom is too excitable. I also use 200. //glom p2g 100 0 0 26.7 LCa3_mit_usb 95 K_mit_usb 28 glom p2g 100 0 0 26.7 LCa3_mit_usb 95 K_mit_usb 200 // I put below values to make mitral fire more and so that glom is less excitable - however it makes mitral double spike methinks. //glom p2g 100 0 0 26.7 LCa3_mit_usb 20 K2_mit_usb 123 Na_mit_usb 134 *set_global RM 1e5 *set_global CM 1e-3 // set such that Rs2p # 5154639 Ohms - use this Ra and the dia and len of dend below to get RA. Don't use this pseudo segment's dia and len //*set_global RA 16.193762 // RA was too large, the lateral dendrite was not responding fast enough - too long time constant. See Margie et al 2000. // Break lateral dendrite into two compartments *set_global RA 16 s2d soma 1 0 0 2 // after splitting into two, the electrotonic lengths have changed now. *set_global RA 1e-4 *set_global CM 0.01 *set_global RM 10 // Using Ra above and l and dia for dend below to get RA + using RM and dia of dend, lambda = 600microns. So electrotonic L of dend = 1/6. // Compare with lambda of Upi's cell which is 1600 microns, and typical dendrite length is 850microns, hence L=0.5. // Unlike BBmit1993, Davison doesn't have these LCa3_mit_usb and K_mit_usb in the dendrite! //dend s2d 100 0 0 170.9 LCa3_mit_usb 4 K_mit_usb 8.5 K2_mit_usb 226 Na_mit_usb 330 dend s2d 100 0 0 170.9 LCa3_mit_usb 4 K_mit_usb 8.5 K2_mit_usb 226 Na_mit_usb 330 *set_global RM 1e5 *set_global CM 1e-3 // set such that Rs2p # 5154639 Ohms - use this Ra and the dia and len of dend below to get RA. Don't use this pseudo segment's dia and len //*set_global RA 16.193762 // RA was too large, the lateral dendrite was not responding fast enough - too long time constant. See Margie et al 2000. // Break lateral dendrite into two compartments *set_global RA 8 //s2d2 dend 1 0 0 2 *set_global RA 1e-4 *set_global CM 0.01 *set_global RM 10 // Unlike BBmit1993, Davison doesn't have these LCa3_mit_usb and K_mit_usb in the dendrite! //dend2 s2d2 50 0 0 170.9 LCa3_mit_usb 4 K_mit_usb 8.5 K2_mit_usb 226 Na_mit_usb 330