Since the transcription factor specificity protein 1 (Sp1) is involved in TGF-β1-stimulated alpha 2(I)-collagen transcription, and connective tissue growth factor (CTGF) participates in the regulation of cardiac fibrosis and heart failure [32], we examined the induction of SP1 and CTGF by I/R injury. Here, CCN2 is linked to heart failure.