KNG1 and angina unstable: Our results demonstrated that plasma level and activity of PRCP and the levels of Ang-(1–7) and BK-(1–9) were increased in patients with ST-segment–elevated AMI and primary PCI, as compared with healthy participants and those with unstable angina, suggesting that the PRCP–Ang-(1–7)/BK-(1–9) axis might be involved in the pathogenesis of myocardial I/R injury.