FIGURE 10.

Restitution properties. The myocyte is paced at a constant cycle length for 5 min followed by a premature stimulus applied at varying diastolic intervals (DI). (A) Representative changes to AP, I_Ca(L), and [Ca²⁺]_i for five different DIs (50 ms, 150 ms, 250 ms, 350 ms, and 450 ms) after pacing at CL = 500 ms. (B) Summary of restitution behavior for a myocyte paced at three different cycle lengths (CL = 300, 500, and 1000 ms). Δ[Ca²⁺]_i is the difference between peak [Ca²⁺]_i and the [Ca²⁺]_i just before application of the premature stimulus.