Model Mathematics

Component: environment

Component: cell

FonRT=FR⁢T past=⌊timestim_period⌋⁢stim_period i_Stim=stim_amplitudeiftime-past≥stim_offset∧time-past≦stim_offset+stim_duration0otherwise I_tot=i_Na+i_Ca+i_to+i_Kr+i_Ks+i_K1+i_NaCa+i_NaK+i_b_Na+i_b_Ca+i_Stim ddtimeV=dVdt dVdt=V_hold-V1ifV_clamp=1∧time≦500∨time>800V_step-V1ifV_clamp=1∧time>500∧time≦800-1⁢I_tototherwise

Component: INa

i_Na=g_Na⁢m3⁢h⁢j⁢V-E_Na E_Na=ln⁡NaoNaiFonRT

Component: INa_m_gate

alpha_m=0.32⁢V+47.131-ⅇ-0.1⁢V+47.13if|V+47.13|>0.0013.2otherwise beta_m=0.08⁢ⅇ-V11 ddtimem=alpha_m⁢1-m-beta_m⁢m

Component: INa_h_gate

alpha_h=0.135⁢ⅇ80+V-6.8ifV<-400otherwise beta_h=3.56⁢ⅇ0.079⁢V+3.1e5⁢ⅇ0.35⁢VifV<-4010.13⁢1+ⅇ-V+10.6611.1otherwise ddtimeh=alpha_h⁢1-h-beta_h⁢h

Component: INa_j_gate

alpha_j=-127140⁢ⅇ0.244⁢V-3.474e-5⁢ⅇ-0.04391⁢V⁢V+37.781+ⅇ0.311⁢V+79.23ifV<-400otherwise beta_j=0.1212⁢ⅇ-0.01052⁢V1+ⅇ-0.1378⁢V+40.14ifV<-400.3⁢ⅇ-2.535e-7⁢V1+ⅇ-0.1⁢V+32otherwise ddtimej=alpha_j⁢1-j-beta_j⁢j

Component: ICa

i_Ca=g_Ca_max⁢d⁢f⁢f_Ca⁢V-E_Ca E_Ca=ln⁡CaoCai2⁢FonRT

Component: ICa_d_gate

alpha_d=14.985916.6813⁢2⁢π⁢ⅇ-V-22.3616.681322 beta_d=0.1471-5.314.93⁢2⁢π⁢ⅇ-V-6.274414.9322 ddtimed=alpha_d⁢1-d-beta_d⁢d

Component: ICa_f_gate

alpha_f=6.872e-31+ⅇV-6.15466.1223 beta_f=0.0687⁢ⅇ-0.1081⁢V+9.8255+0.01121+ⅇ-0.2779⁢V+9.8255+5.474e-4 ddtimef=alpha_f⁢1-f-beta_f⁢f

Component: ICa_f_Ca_gate

f_Ca=Km_CaKm_Ca+Cai

Component: Ito

g_to_max=0.3iffailing=00.191otherwise i_to=g_to_max⁢r⁢t⁢V-E_to E_to=ln⁡0.043⁢Nao+Ko0.043⁢Nai+KiFonRT

Component: Ito_r_gate

ddtimer=alpha_r⁢1-r-beta_r⁢r alpha_r=0.5266⁢ⅇ-0.0166⁢V-42.29121+ⅇ-0.0943⁢V-42.2912 beta_r=5.186e-5⁢V+0.5149⁢ⅇ-0.1344⁢V-5.00271+ⅇ-0.1348⁢V-5.186e-5

Component: Ito_t_gate

ddtimet=alpha_t⁢1-t-beta_t⁢t alpha_t=5.612e-5⁢V+0.0721⁢ⅇ-0.173⁢V+34.25311+ⅇ-0.1732⁢V+34.2531 beta_t=1.215e-4⁢V+0.0767⁢ⅇ-1.66e-9⁢V+34.02351+ⅇ-0.1604⁢V+34.0235

Component: IKs

i_Ks=g_Ks_max⁢Xs2⁢V-E_Ks E_Ks=ln⁡0.01833⁢Nao+Ko0.01833⁢Nai+KiFonRT

Component: IKs_Xs_gate

ddtimeXs=alpha_Xs⁢1-Xs-beta_Xs⁢Xs alpha_Xs=3.013e-31+ⅇ7.4454-V+1014.3171 beta_Xs=5.87e-31+ⅇ5.95+V+1015.82

Component: IKr

i_Kr=g_Kr_max⁢Xr⁢rik⁢V-E_K E_K=ln⁡KoKiFonRT rik=11+ⅇV+2623

Component: IKr_Xr_gate

ddtimeXr=alpha_Xr⁢1-Xr-beta_Xr⁢Xr alpha_Xr=0.005⁢ⅇ5.266e-4⁢V+4.0671+ⅇ-0.1262⁢V+4.067 beta_Xr=0.016⁢ⅇ1.6e-3⁢V+65.661+ⅇ0.0783⁢V+65.66

Component: IK1

g_K1_max=2.5iffailing=02otherwise i_K1=g_K1_max⁢K1_infinity⁢V-E_K1 E_K1=ln⁡KoKiFonRT

Component: IK1_K1_gate

K1_infinity=alpha_K1alpha_K1+beta_K1 alpha_K1=0.11+ⅇ0.06⁢V-E_K1+200 beta_K1=3⁢ⅇ2e-4⁢V+100+-E_K1+1⁢ⅇ0.1⁢V-10+E_K11+ⅇ-0.5⁢V-E_K1

Component: ICab

g_b_Ca_max=0.00085iffailing=00.0013otherwise i_b_Ca=g_b_Ca_max⁢V-E_Ca

Component: INab

g_b_Na_max=0.001iffailing=00otherwise i_b_Na=g_b_Na_max⁢V-E_Na

Component: INaK

I_NaK_max=1.3iffailing=00.75otherwise f_NaK=11+0.1245⁢ⅇ-0.1⁢V⁢FonRT+0.0365⁢sigma⁢ⅇ-V⁢FonRT sigma=17⁢ⅇNao67.3-1 i_NaK=I_NaK_max⁢f_NaK⁢11+K_mNaiNai1.5⁢KoKo+K_mKo

Component: INaCa

K_NaCa=1000iffailing=01650otherwise i_NaCa=K_NaCa⁢1K_mNa3+Nao3⁢1K_mCa+Cao⁢11+K_sat⁢ⅇeta-1⁢V⁢FonRT⁢ⅇeta⁢V⁢FonRT⁢Nai3⁢Cao-ⅇeta-1⁢V⁢FonRT⁢Nao3⁢Cai

Component: Irel

ddtimeAPtrack=100⁢1-APtrack-0.5⁢APtrackifdVdt>150-0.5⁢APtrackotherwise ddtimeAPtrack2=100⁢1-APtrack2-0.5⁢APtrack2ifAPtrack<0.2∧APtrack>0.18-0.5⁢APtrack2otherwise ddtimeAPtrack3=100⁢1-APtrack3-0.5⁢APtrack3ifAPtrack<0.2∧APtrack>0.18-0.01⁢APtrack3otherwise ddtimeCainfluxtrack=-Cm⁢i_Ca-i_NaCa+i_b_Ca2⁢V_myo⁢FifAPtrack>0.20ifAPtrack2>0.01∧APtrack≦0.2-0.5⁢Cainfluxtrackotherwise ddtimeOVRLDtrack=0⁢50⁢1-OVRLDtrackif11+K_mCSQNCa_JSR>CSQNthresh∧OVRLDtrack3<0.37∧APtrack3<0.37-0⁢0.5⁢OVRLDtrackotherwise ddtimeOVRLDtrack2=0⁢50⁢1-OVRLDtrack2ifOVRLDtrack>Logicthresh∧OVRLDtrack2<Logicthresh-0⁢0.5⁢OVRLDtrack2otherwise ddtimeOVRLDtrack3=0⁢50⁢1-OVRLDtrack3ifOVRLDtrack>Logicthresh∧OVRLDtrack3<Logicthresh-0⁢0.01⁢OVRLDtrack3otherwise G_rel=1⁢G_rel_max⁢Cainfluxtrack-delta_Ca_ithK_mrel+Cainfluxtrack-delta_Ca_ith⁢1-APtrack2⁢APtrack2ifCainfluxtrack>delta_Ca_ith0⁢G_rel_overload⁢1-OVRLDtrack2⁢OVRLDtrack2ifCainfluxtrack≦delta_Ca_ith∧OVRLDtrack2>00otherwise i_rel=G_rel⁢Ca_JSR-Cai

Component: Iup

I_up_max=0.0045iffailing=00.0015otherwise i_up=I_up_max⁢CaiCai+K_mup

Component: Ileak

K_leak=0.00026iffailing=00.00017otherwise i_leak=K_leak⁢Ca_NSR

Component: Itr

i_tr=1⁢Ca_NSR-Ca_JSRtau_tr

Component: calcium_buffers_in_the_myoplasm

Cai_bufc=11+buffon⁢CMDN_max⁢K_mCMDNK_mCMDN+Cai2+Tn_max⁢K_mTnK_mTn+Cai2

Component: calcium_buffers_in_the_JSR

Ca_JSR_bufc=11+CSQN_max⁢K_mCSQNK_mCSQN+Ca_JSR2

Component: Ionic_concentrations

volume=π⁢preplength⁢radius2 V_myo=0.68⁢volume V_NSR=0.0552⁢volume V_JSR=0.0048⁢volume ddtimeNai=-1⁢Cm⁢i_Na+i_b_Na+i_NaCa⁢3+i_NaK⁢3V_myo⁢F ddtimeKi=-1⁢Cm⁢i_to+i_Kr+i_K1+i_Stim+i_Ks-2⁢i_NaKV_myo⁢F ddtimeCai=Cai_bufc⁢-Cm⁢i_Ca-2⁢i_NaCa+i_b_Ca2⁢V_myo⁢F+i_rel⁢V_JSRV_myo+i_leak-i_up⁢V_NSRV_myo ddtimeCa_JSR=Ca_JSR_bufc⁢i_tr-i_rel ddtimeCa_NSR=-1⁢i_leak+V_JSRV_NSR⁢i_tr-i_up

Component: transmembrane_currents

Component: intracellular_currents

Component: Ions_n_reversal_potentials