xs1ss 1 1 V 1.5 16.7 xs2ss xs1ss tauxs1 1 0.0000719 0.148 0.000131 0.0687 V 30 0.001 0.0687 1 0.0000719 V 30 1 0.148 V 30 0.000131 V 30 0.0687 V 30 1 tauxs2 4 tauxs1 gksx 1 0.8 1 0.5 Ca_i 3 xiks gks gksx xs1 xs2 V eks time xs1 xs1ss xs1 tauxs1 time xs2 xs2ss xs2 tauxs2