Objectives: The aim of the study was to evaluate the effects of oral administration of clinical dose of beraprost for feline CKD in healthy cats, and also to examine whether NOS inhibition reversed them. Methods: A placebo-controlled pharmacological sequential design study was carried out to assess plasma aldosterone and renin concentrations, mean blood pressure, heart rate, renal plasma flow, and renal vascular resistance. Results: Beraprost reduced plasma aldosterone when compared to the placebo (P < 0.05); this was reversed when NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME) was added to beraprost treatment (P < 0.01). No differences in the plasma renin concentration or hemodynamic parameters were detected between beraprost and placebo. The correlation ratios (η2) showed opposite relationships between beraprost and added L-NAME effects on aldosterone concentration, mean blood pressure, heart rate, renal plasma flow, and renal vascular resistance (P < 0.001). Conclusions: In healthy cats, the clinical dose of beraprost suppresses plasma concentration of aldosterone, which can be reversed by inhibition of NOS.