/*-------------------------------------------------------------- TEMPLATE FILE FOR DEFINING THALAMOCORTICAL NEURONS -------------------------------------------------- One compartment model and currents derived from: McCormick, D.A. and Huguenard, J.R. A model of the electrophysiological properties of thalamocortical relay neurons. J. Neurophysiology 68: 1384-1400, 1992. - passive: parameters idem Rinzel - HH: Traub with higher threshold - IT: m2h, nernst, tau_h modified with double exponential - Ih: Huguenard with Ca++ dependence added, Ca++-binding protein - Ca++: simple decay, faster than McCormick This model is described in detail in: Destexhe, A., Bal, T., McCormick, D.A. and Sejnowski, T.J. Ionic mechanisms underlying synchronized oscillations and propagating waves in a model of ferret thalamic slices. Journal of Neurophysiology 76: 2049-2070, 1996. See also http://www.cnl.salk.edu/~alain , http://cns.fmed.ulaval.ca Alain Destexhe, Salk Institute and Laval University, 1995 --------------------------------------------------------------*/ print " " print " << defining template for one-compartment sTC cell >> " print " " begintemplate sTC // create a new template object public soma , kl create soma[1] // one compartment of about 29000 um2 soma { nseg = 1 diam = 96 L = 96 cm = 1 } objectvar kl proc init() { local v_potassium, v_sodium objectvar kl kl = new kleak() v_potassium = -100 // potassium reversal potential v_sodium = 50 // sodium reversal potential soma { diam = 96 // geometry L = 96 // so that area is about 29000 um2 nseg = 1 Ra = 100 insert pas // leak current e_pas = -70 // from Rinzel g_pas = 1e-5 kl.loc(0.5) // K-leak Erev_kleak = v_potassium kl.gmax = 0.004 // (uS) // conversion: x(uS) = x(mS/cm2)*29000e-8*1e3 // = x(mS/cm2) * 0.29 insert hh2 // Hodgin-Huxley INa and IK ek = v_potassium ena = v_sodium vtraub_hh2 = -25 // High threshold to simulated IA gnabar_hh2 = 0.09 gkbar_hh2 = 0.01 insert it // T-current cai = 2.4e-4 cao = 2 eca = 120 gcabar_it = 0.002 insert iar // h-current eh = -40 // reversal nca_iar = 4 // nb of binding sites for Ca++ on protein k2_iar = 0.0004 // decay of Ca++ binding on protein cac_iar = 0.002 // half-activation of Ca++ binding nexp_iar = 1 // nb of binding sites on Ih channel k4_iar = 0.001 // decay of protein binding on Ih channel Pc_iar = 0.01 // half-activation of binding on Ih channel ginc_iar = 2 // augm of conductance of bound Ih ghbar_iar = 2e-5 // low Ih for slow oscillations insert cad // calcium decay depth_cad = 1 taur_cad = 5 cainf_cad = 2.4e-4 kt_cad = 0 // no pump } print " " print "<< sTC: passive, Kleak, INa, IK, IT, Ih-CAM and Ca++ decay inserted >>" print " " } endtemplate sTC