Click it plus tunel assay kits for in situ apoptosis detection

TUNEL assays were performed on deparaffinized heart sections using a Click-iT^™ Plus TUNEL Assay Kits for In Situ Apoptosis Detection (Invitrogen, C10617), according to the manufacturer’s instruction. The samples were then co-stained with Alexa Fluor Plus 647 Phalloidin (Invitrogen, A30107) for 1 hour at 37°C to visualize cells in tissue sections. For positive controls, sample tissues were treated with DNase I prior to the TUNEL assay. The number of cells with positive staining in the TUNEL assay (TUNEL⁺ cells) was determined using sections from three hearts per genotype. TUNEL positive cell counts between two groups were compared using Wilcoxon rank sum tests in R.