Figure 3.

IL-1R deficiency produces slight differences in APD but not enough to prevent the susceptibility to ventricular arrhythmias in CCC. Wild-type (WT) and Il-1r ^−/− mice (C57BL/6 background) were infected with the Colombian strain of T. cruzi (sum of two independent experiments with similar parasitemias, 50 and 200 parasites/inoculum) and analyzed at 270 dpi. Cardiac action potential (AP) was evaluated from the endocardial layer of the left ventricle ex vivo heart to compare noninfected and infected mice. (A) Representative whole heart AP traces. (B) AP duration at 30%, 50%, 70%, and 90% of repolarization (4–14 mice per group). (C) Ventricular arrhythmic events induced by the S₁–S₂ protocol (4–14 mice per group, data represent mean ± SEM). (D) The prevalence of ventricular arrhythmic events in whole hearts from groups of mice.