Acta physiologica Hungarica, cilt.100, sa.3, ss.280-8, 2013 (SCI-Expanded)
Objectives: Des-Arg(9)-bradykinin and bradykinin-potentiating peptide C (BPPC) may contribute to the regulation of cardiovascular function. Therefore, we studied effects of these peptides on coronary perfusion pressure (CPP), heart rate, left ventricular developed pressure (LVDP) and maximum rate of increase of left ventricular pressure (+dP/dt(max)). Methods: The isolated rat hearts were perfused with modified Krebs-Henseleit solution. Results: Infusion of 10, 100 and 1000 nM Des-Arg(9)-bradykinin decreased CPP (-13.6, -14.8 and -19.0%), LVDP (-16.5, -21.0 and -30.7%) and +dP/dt(max) (-11.8, -17.8 and -23.7%), respectively (p < 0.001). Ten or 100 nM Des-Arg(9)-bradykinin did not alter heart rate, but 1000 nM increased it (+11.3%, p < 0.01). One, 10 and 100 nM BBPC reduced CPP (-16.3, -28.5 and -47.5%), LVDP (-12.6, -19.6 and -21.3%) and +dP/dt(max) (-8.7, -18.6 and -20.3%), respectively (p < 0.001). BPPC increased heart rate at 1 nM (+9.6%, p < 0.05) and at 10 nM (+14.2%, p < 0.01), however 100 nM decreased it (-15.3%, p < 0.001). Conclusions: This study evidences that Des-Arg(9)-bradykinin and BPPC possess vasodilatory effect with modest negative inotropic action. Furthermore, high-dose of Des-Arg(9)-bradykinin and low-dose of BPPC may produce a tachycardic action, but high dose of BBPC may cause a bradycardic action.