Kinin antagonist blunts the diuretic effect of furosemide in deoxycorticosterone-treated rats

Furosemide at a dose of 3 mg/kg body wt increased urinary volume (vehicle: 12.8 +/- 0.6; furosemide: 42.4 +/- 2.6 ml/8h, p < 0.01) and urinary sodium excretion (vehicle: 0.9 +/- 0.1; furosemide: 5.0 +/- 0.4 mM/8h, p < 0.01) in deoxycorticosterone-treated rats. These effects were associated to a decrease in mean blood pressure (from 122 +/- 4 to 113 +/- 3 mmHg, p < 0.01) and renal vascular resistances (from 15.6 +/- 0.6 to 14.3 +/- 0.7 RU, p < 0.05). The B2-receptor antagonist D-Arg[Hyp3,Thi5,D-Tic7,Oic8]-bradykinin significantly blunted the diuretic and natriuretic effect of furosemide and completely prevented the decrease in blood pressure and renal vascular resistances. The renal kallikrein-kinin system may modulate the diuretic and hemodynamic effects of furosemide in conditions of increased mineralcorticoid activity.