鈉鈣離子交換通道是迅速移除生物細胞內高濃度鈣離子的重要機制。本篇論文建立一個簡化的數學模型，從通道內電位分布的演變，探討鈉鈣離子序列交換的行為。

The sodium-calcium exchanger is an ion channel that removes calcium very rapidly from cells. By using both analytical equation at the binding site and a molecular-continuum model throughout the entire domain under a reduced model, we are able to explain mathematically the exchange reaction and the cooperativity of sequential bindings and releases of Na+ and Ca2+ ions.

1. Introduction 1
2. Material and Methods 2
2.1. Protein Data Bank (PDB) 2
2.2. Binding Sites 4
2.3. Scenario of Ion Exchange 6
2.4. Channel Geometry 7
2.5. Analytical Electrical Potential at the Binding Sites 9
2.6. A Molecular-Continuum Model for Potential Profiles 9
3. Main Results 10
3.1. Analytical Potential Scenario at the Binding Sites 10
3.2. Potential Profiles inside the Channels 11
4. Conclusion and Outlook 14
5. References 15

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