The increased interstitial fibrosis in B2–/– mice was associated with decreased activity of MMP‐2 suggesting the protective role of bradykinin and MMP‐2.73 Similarly, involvement of B2R in the release of MMP‐2 from tracheal smooth muscle cells of guinea pig has been reported.74 In a recent study, B1R agonist, Lys‐des[Arg9]‐bradykinin (LDBK), increased the proliferation of oestrogen‐sensitive breast cancer cells. The gene discussed is MMP2; the disease is breast cancer.