Figure 10.

Metabolic efficiency of the AP is reduced as I_KAHP is activated. (A) Total Na⁺ load Q_total, (B) minimal Na⁺ load Q_min, and (C) Na⁺ entry ratio are respectively calculated for each AP during the activation of I_KAHP with p = 0.4 and 0.6. Top panels show the response of V_S (gray) and I_KAHP (pink) recorded in the model III with each value of p. Note that our examination starts from the 2nd AP, since I_KAHP is totally unactivated during the 1st AP. $I_{\mathrm{\text{D}}}=2\mu \mathrm{\text{A}}/\mathrm{\text{c}}{\mathrm{\text{m}}}^{\mathrm{\text{2}}}$ and $g_{\mathrm{\text{c}}}=0.6\mathrm{\text{mS}}/\mathrm{\text{c}}{\mathrm{\text{m}}}^{\mathrm{\text{2}}}$.