Fig 3. Effect of ISO or ANP on Ca²⁺ sparks in sham and failing cardiomyocytes.

A. Representative data for diastolic Ca²⁺ sparks in sham and failing cardiomyocytes. B. Bar graph representation of the data in Fig 3A. The bars indicate the means ± SE. Each group included 20–30 cells. At least 4 cells were evaluated for each preparation. Notably, ISO-induced aberrant diastolic Ca²⁺ sparks were inhibited by 10 nM ANP, but upon the addition of H₂O₂ (25 μM), aberrant diastolic Ca²⁺ sparks reappeared in the failing cardiomyocytes.