This is the readme.txt for the models associated with the paper

Silva J, Rudy Y. Subunit interaction determines IKs participation
 in cardiac repolarization and repolarization reserve. 
Circulation 2005;112:1384-91.
The results reproduce Figure 3C in the paper.

BACKGROUND: The role of IKs, the slow delayed rectifier K+ 
current, in cardiac ventricular repolarization has been a subject 
of debate. METHODS AND RESULTS: We develop a detailed Markov 
model of IKs and its alpha-subunit KCNQ1 and examine their 
kinetic properties during the cardiac ventricular action 
potential at different rates. We observe that interaction 
between KCNQ1 and KCNE1 (the beta-subunit) confers kinetic 
properties on IKs that make it suitable for participation in 
action potential repolarization and its adaptation to rate 
changes; in particular, the channel develops an available reserve
of closed states near the open state that can open rapidly on 
demand. CONCLUSIONS: Because of its ability to form an available 
reserve, IKs can function as a repolarization reserve when IKr, 
the rapid delayed rectifier, is reduced by disease or drug and 
can prevent excessive action potential prolongation and 
development of arrhythmogenic early afterdepolarizations.

These kinetic parameters are shown in Data supplement of 
the paper:

To run the models:
XPP: start with the command

xpp ode\IKs_Mar.ode

To make a trace similar to one in fig 3C of the paper:
Mouse click on Initialconds, and then (G)o.

To run the full family of voltage-clamp traces, 
click Range over, change the value to vtest_1.
Similarly set Steps:10, Start:-50, End:60, Reset Storage:N,
Cycle color:y, and click Ok.

This produces a graph like:

To run deactivation protocol, please change the value to vtest_2.
and then select a voltage protocol from Steps, Start and End.

Regarding xpp program, please contact with 
Bard Ermentrout's website, which 
describes how to get and use xpp.

The model files were submitted by:

Dr. Sheng-Nan Wu, Han-Dong Chang, Jiun-Shian Wu
Department of  Physiology
National Cheng Kung University Medical College
Tainan 70101, Taiwan