Wild‐type mice were randomly divided into 4 groups treated with rmIL‐11 or IL‐11 neutralizing antibody with or without Ang II infusion. A, Representative hematoxylin and eosin (H&E) and picrosirius red staining of the thoracic aorta tissues. Bar=50 µm. B through D, Quantitative analysis of wall thickness (B), wall area (C), and collagen area (D). E, Systolic blood pressure of the 4 groups. F, Representative immunofluorescence staining and quantitative analysis of ER‐TR7 (red), α‐smooth muscle actin (ACTA2) (green), CD68 (green), and Krüppel‐like factor 15 (KLF15) (red) in thoracic aorta. The 4′,6‐diamidino‐2‐phenylindole was used to stain the nucleus in blue. Bar=50 µm. G, The mRNA levels of KLF15 (1.00‐, 0.47‐, 0.39‐, and 0.40‐fold), collagen, type I, α 1 (COL1a1) (1.00‐, 2.85‐, 0.81‐, and 3.70‐fold), collagen, type III, α 1 (COL3a1) (1.00‐, 2.69‐, 0.85‐, and 6.67‐fold), interleukin‐6 (IL‐6) (1.00‐, 1.75‐, 0.23‐, and 1.95‐fold), and chemokine (C‐C motif) ligand 2 (CCL2) (1.00‐, 1.83‐, 0.39‐, and 2.76‐fold) were measured by quantitative reverse transcription–polymerase chain reaction. A indicates adventitia. *P< 0.05, **P< 0.01, and ***P< 0.001.