(A) Different chemistries of miR-21 inhibitors (modifications of oligonucleotides are indicated with corresponding colors in the key). (B) miR-21 expression 48 hours and 19 days after treatment (21 days after TAC) with different miR-21 inhibitors (10–80 mg/kg). (C) Efficacy of different miR-21 inhibitors in a mouse model of left ventricular pressure overload (TAC) on left ventricular fibrosis formation, left ventricular mass, and ejection fraction. The different miR-21 oligonucleotide inhibitors have been applied twice on two consecutive days (#1 and #2). Original magnification, ×200. Ant-21, anti–miR-21; Chol, cholesterol. Data are mean ± SEM. *P < 0.05, **P < 0.01.