Table 2 Functions associated with activation and inactivation variables for system ( 1a )–( 1g ). We use the variable y when an expression corresponds to a set of variables
Gating variables | Steady-state activation and inactivation | Time constants |
|---|---|---|
\(m_{\mathrm{Na}}\) | \(y_{\infty}(V)= 1/(1+\exp (-(V-V_{y1/2})/k_{y}))\) | \(\tau_{y}(V)=\tau_{y\max}/\cosh (-(V-V_{\tau y1/2})/ k_{\tau y})\) |
\(h_{\mathrm{Na}}\) | ||
\(m_{\mathrm{NaP}}\) | ||
\(h_{\mathrm{Na}}\) | ||
\(m_{\mathrm{Ca}}\) | \(\tau_{m_{\mathrm{Ca}}}=0.5~\mbox{ms}\) | |
\(h_{\mathrm{Ca}}\) | \(\tau_{h_{\mathrm{Ca}}}=18~\mbox{ms}\) | |
\(m_{\mathrm{K}}\) | \({m_{\mathrm{K}}}_{\infty}= \alpha _{\infty}/(\alpha_{\infty}+\beta_{\infty})\) | \(\tau_{m_{\mathrm {K}}}=1/(\alpha_{\infty}+\beta_{\infty})\) |
\(\alpha_{\infty}= A_{\alpha }\cdot(V+B_{\alpha})/(1-\exp(-(V+B_{\alpha})/k_{\alpha}))\), \(\beta _{\infty}=A_{\beta}\cdot\exp(-(V+B_{\beta})/k_{\beta})\) | ||
\(m_{\mathrm{CAN}}\) | \(m_{\mathrm{CAN}}=1/(1+(K_{\mathrm {CAN}}/\mathrm{Ca}_{\mathrm{i}})^{n})\) | |