Model Mathematics

Component: environment

Component: membrane

i_Stim=stim_amplitudeiftime≥stim_start∧time≦stim_end∧time-stim_start-⌊time-stim_startstim_period⌋⁢stim_period≦stim_duration0otherwise ddtimeV=-1⁢1⁢i_Na+i_Ca+i_Ca_K+i_Kr+i_Ks+i_to1+i_K1+i_Kp+i_NaCa+i_NaK+i_p_Ca+i_Na_b+i_Ca_b+i_StimC_sc

Component: fast_sodium_current

E_Na=R⁢TF⁢ln⁡NaoNai i_Na=g_Na⁢m3⁢h⁢j⁢V-E_Na

Component: fast_sodium_current_m_gate

E0_m=V+47.13 alpha_m=10000.1-0.005⁢E0_mif|E0_m|<0.00001320⁢E0_m1-ⅇ-0.1⁢E0_motherwise beta_m=80⁢ⅇ-V11 ddtimem=alpha_m⁢1-m-beta_m⁢mifV≥-900otherwise

Component: fast_sodium_current_h_gate

alpha_h=135⁢ⅇ80+V-6.8ifV<-400otherwise beta_h=3560⁢ⅇ0.079⁢V+310000⁢ⅇ0.35⁢VifV<-4010000.13⁢1+ⅇV+10.66-11.1otherwise ddtimeh=alpha_h⁢1-h-beta_h⁢h

Component: fast_sodium_current_j_gate

alpha_j=1000⁢-127140⁢ⅇ0.2444⁢V+0.00003474⁢ⅇ-0.04391⁢V⁢V+37.781+ⅇ0.311⁢V+79.23ifV<-400otherwise beta_j=121.2⁢ⅇ-0.01052⁢V1+ⅇ-0.1378⁢V+40.14ifV<-40300⁢ⅇ-0.0000002535⁢V1+ⅇ-0.1⁢V+32otherwise ddtimej=alpha_j⁢1-j-beta_j⁢j

Component: rapid_activating_delayed_rectifiyer_K_current

E_K=R⁢TF⁢ln⁡KoKi f_Ko=Ko4 R_V=11+1.4945⁢ⅇ0.0446⁢V i_Kr=g_Kr⁢f_Ko⁢R_V⁢X_kr⁢V-E_K

Component: rapid_activating_delayed_rectifiyer_K_current_X_kr_gate

K12=ⅇ-5.495+0.1691⁢V K21=ⅇ-7.677-0.0128⁢V X_kr_inf=K12K12+K21 tau_X_kr=0.001K12+K21+tau_factor⁢0.027 ddtimeX_kr=X_kr_inf-X_krtau_X_kr

Component: slow_activating_delayed_rectifiyer_K_current

E_Ks=R⁢TF⁢ln⁡Ko+0.01833⁢NaoKi+0.01833⁢Nai i_Ks=g_Ks⁢X_ks2⁢V-E_Ks

Component: slow_activating_delayed_rectifiyer_K_current_X_ks_gate

X_ks_infinity=11+ⅇ-V-24.713.6 tau_X_ks=0.0010.0000719⁢V-101-ⅇ-0.148⁢V-10+0.000131⁢V-10ⅇ0.0687⁢V-10-1 ddtimeX_ks=X_ks_infinity-X_kstau_X_ks

Component: transient_outward_potassium_current

i_to1=g_to1⁢X_to1⁢Y_to1⁢V-E_K

Component: transient_outward_potassium_current_X_to1_gate

alpha_X_to1=45.16⁢ⅇ0.03577⁢V beta_X_to1=98.9⁢ⅇ-0.06237⁢V ddtimeX_to1=alpha_X_to1⁢1-X_to1-beta_X_to1⁢X_to1

Component: transient_outward_potassium_current_Y_to1_gate

alpha_Y_to1=5.415⁢ⅇ-V+33.551+0.051335⁢ⅇ-V+33.55 beta_Y_to1=5.415⁢ⅇV+33.551+0.051335⁢ⅇV+33.55 ddtimeY_to1=alpha_Y_to1⁢1-Y_to1-beta_Y_to1⁢Y_to1

Component: time_independent_potassium_current

i_K1=g_K1⁢K1_infinity_V⁢KoKo+K_mK1⁢V-E_K

Component: time_independent_potassium_current_K1_gate

K1_infinity_V=12+ⅇ1.5⁢FR⁢T⁢V-E_K

Component: plateau_potassium_current

i_Kp=g_Kp⁢Kp_V⁢V-E_K

Component: plateau_potassium_current_Kp_gate

Kp_V=11+ⅇ7.488-V5.98

Component: Na_Ca_exchanger

i_NaCa=K_NaCa⁢5000K_mNa3+Nao3⁢K_mCa+Cao⁢1+K_sat⁢ⅇeta-1⁢V⁢FR⁢T⁢ⅇeta⁢V⁢FR⁢T⁢Nai3⁢Cao-ⅇeta-1⁢V⁢FR⁢T⁢Nao3⁢Cai

Component: sodium_potassium_pump

f_NaK=11+0.1245⁢ⅇ-0.1⁢V⁢FR⁢T+0.0365⁢sigma⁢ⅇ-V⁢FR⁢T sigma=17⁢ⅇNao67.3-1 i_NaK=I_NaK⁢f_NaK1+K_mNaiNai1.5⁢KoKo+K_mKo

Component: sarcolemmal_calcium_pump

i_p_Ca=I_pCa⁢CaiK_mpCa+Cai

Component: calcium_background_current

E_Ca=R⁢T2⁢F⁢ln⁡CaoCai i_Ca_b=g_Cab⁢V-E_Ca

Component: sodium_background_current

i_Na_b=g_Nab⁢V-E_Na

Component: L_type_Ca_current

i_Ca=i_Ca_max⁢y⁢O+O_Ca i_Ca_K=p_prime_k1⁢1⁢y⁢O+O_Ca⁢V⁢F2R⁢T⁢Ki⁢ⅇV⁢FR⁢T-KoⅇV⁢FR⁢T-1 p_prime_k=P_K1+i_Ca_maxi_Ca_half i_Ca_max=P_Ca1⁢1⁢4⁢V⁢F2⁢1000R⁢T⁢0.001⁢ⅇ2⁢V⁢FR⁢T-0.341⁢Caoⅇ2⁢V⁢FR⁢T-1 alpha=400⁢ⅇV+210 beta=50⁢ⅇ-V+213 alpha_a=alpha⁢a beta_b=betab gamma=103.75⁢Ca_ss1 ddtimeC0=beta⁢C1+omega⁢C_Ca0-4⁢alpha+gamma⁢C0 ddtimeC1=4⁢alpha⁢C0+2⁢beta⁢C2+omegab⁢C_Ca1-beta+3⁢alpha+gamma⁢a⁢C1 ddtimeC2=3⁢alpha⁢C1+3⁢beta⁢C3+omegab2⁢C_Ca2-beta⁢2+2⁢alpha+gamma⁢a2⁢C2 ddtimeC3=2⁢alpha⁢C2+4⁢beta⁢C4+omegab3⁢C_Ca3-beta⁢3+alpha+gamma⁢a3⁢C3 ddtimeC4=alpha⁢C3+g⁢O+omegab4⁢C_Ca4-beta⁢4+f+gamma⁢a4⁢C4 ddtimeO=f⁢C4-g⁢O ddtimeC_Ca0=beta_b⁢C_Ca1+gamma⁢C0-4⁢alpha_a+omega⁢C_Ca0 ddtimeC_Ca1=4⁢alpha_a⁢C_Ca0+2⁢beta_b⁢C_Ca2+gamma⁢a⁢C1-beta_b+3⁢alpha_a+omegab⁢C_Ca1 ddtimeC_Ca2=3⁢alpha_a⁢C_Ca1+3⁢beta_b⁢C_Ca3+gamma⁢a2⁢C2-beta_b⁢2+2⁢alpha_a+omegab2⁢C_Ca2 ddtimeC_Ca3=2⁢alpha_a⁢C_Ca2+4⁢beta_b⁢C_Ca4+gamma⁢a3⁢C3-beta_b⁢3+alpha_a+omegab3⁢C_Ca3 ddtimeC_Ca4=alpha_a⁢C_Ca3+gprime⁢O_Ca+gamma⁢a4⁢C4-beta_b⁢4+fprime+omegab4⁢C_Ca4 ddtimeO_Ca=fprime⁢C_Ca4-gprime⁢O_Ca

Component: L_type_Ca_current_y_gate

y_infinity=0.81+ⅇV+12.55+0.2 tau_y=20+6001+ⅇV+209.51000 ddtimey=y_infinity-ytau_y

Component: RyR_channel

ddtimeP_C1=-k_a_plus⁢Ca_ssn⁢P_C1+k_a_minus⁢P_O1 ddtimeP_O1=k_a_plus⁢Ca_ssn⁢P_C1-k_a_minus⁢P_O1+k_b_plus⁢Ca_ssm⁢P_O1+k_c_plus⁢P_O1+k_b_minus⁢P_O2+k_c_minus⁢P_C2 ddtimeP_O2=k_b_plus⁢Ca_ssm⁢P_O1-k_b_minus⁢P_O2 ddtimeP_C2=k_c_plus⁢P_O1-k_c_minus⁢P_C2 J_rel=v1⁢P_O1+P_O2⁢Ca_JSR-Ca_ss

Component: SERCA2a_pump

fb=CaiK_fbN_fb rb=Ca_NSRK_rbN_rb J_up=K_SR⁢Vmaxf⁢fb-Vmaxr⁢rb1+fb+rb

Component: intracellular_Ca_fluxes

J_tr=Ca_NSR-Ca_JSRtau_tr J_xfer=Ca_ss-Caitau_xfer J_trpn=HTRPN_tot⁢J_HTRPNCa+LTRPN_tot⁢J_LTRPNCa J_HTRPNCa=ddtimeHTRPNCa ddtimeHTRPNCa=k_htrpn_plus⁢Cai⁢1-HTRPNCa-k_htrpn_minus⁢HTRPNCa J_LTRPNCa=ddtimeLTRPNCa ddtimeLTRPNCa=k_ltrpn_plus⁢Cai⁢1-LTRPNCa-k_ltrpn_minus⁢LTRPNCa

Component: intracellular_ion_concentrations

ddtimeCai=beta_i⁢J_xfer-J_up+J_trpn+2⁢i_NaCa-i_p_Ca+i_Ca_b⁢A_cap⁢12⁢V_myo⁢F ddtimeNai=-0⁢i_Na+i_Na_b+i_NaCa⁢3+i_NaK⁢3⁢A_cap⁢1V_myo⁢F ddtimeKi=-0⁢i_Ca_K+i_Kr+i_Ks+i_K1+i_Kp+i_to1+i_NaK⁢-2⁢A_cap⁢1V_myo⁢F beta_i=11+CMDN_tot⁢K_mCMDNK_mCMDN+Cai2+EGTA_tot⁢K_mEGTAK_mEGTA+Cai2 beta_SS=11+CMDN_tot⁢K_mCMDNK_mCMDN+Ca_ss2+EGTA_tot⁢K_mEGTAK_mEGTA+Ca_ss2 beta_JSR=11+CSQN_tot⁢K_mCSQNK_mCSQN+Ca_JSR2 ddtimeCa_ss=beta_SS⁢J_rel⁢V_JSRV_SS-J_xfer⁢V_myoV_SS-i_Ca⁢A_cap⁢12⁢V_SS⁢F ddtimeCa_JSR=beta_JSR⁢J_tr-J_rel ddtimeCa_NSR=J_up⁢V_myoV_NSR-J_tr⁢V_JSRV_NSR

Component: standard_ionic_concentrations