Calpain-Calcineurin-Nuclear Factor Signaling and the Development of Atrial Fibrillation in Patients with Valvular Heart Disease and Diabetes

Figure 3

Immunohistochemical localization of calpain 2 in atrial cardiomyocytes ((a) AF group, ×200; (b) SR group, ×400). Calpain 2, brown-stained granules, was localized in the cytoplasm of atrial myocytes, but not in endocardium or epicardium. Enhanced expression of calpain 2 was observed in samples from patients with AF compared to those from SR group. AF indicates atrial fibrillation; SR indicates sinus rhythm.

(a)

(b)