ST-115 (ST115) is a potent and specific inhibitor of aminopeptidase P2 (XPNPEP2, APP2) with IC50 of 3.7 nM.ST-115 does not inhibit ACE, neprilysin, or multiple other enzymes, and littile inhibition against Aminopeptidase P1/A/B/N (IC50=600 nM->10 uM).ST-115 can reduce bradykinin degradation, increasing its concentration and protective effects when administered intravenously at the start of reperfusion, reduced damaged area of the heart in a mouse model of myocardial infarction.In a rat model of ischemic stroke, ST-115 reduced functional deficits in a skilled walking test by 60% and reduced brain edema by 51%.ST-115 also reduced brain infarct size by 48% in a major subset of rats with small strokes.