Potassium supplementation increases sodium excretion and nitric oxide production in hypertensive Dahl rats

The present study was designed to investigate whether antihypertensive and natriuretic effects of K were achieved by elevation of nitric oxide (NO) pr oduction in Dahl salt-sensitive (DS) rats. The rats were placed in individu al metabolic cage and fed a high sodium diet with or without K supplementat ion for 4 weeks. K supplementation counteracted the blood-pressure raising effect of NaCl. K supplementation significantly enhanced sodium excretion a nd reduced sodium retention, increased the urinary nitrite plus nitrate exc retion and kidney constitutive NO synthase activity in salt-loaded DS rats. These effect did not occur in the rats fed a low sodium diet with K supple mentation. These results suggest that K supplementation attenuates developm ent of hypertension with reduction of sodium retension in salt-loaded DS ra ts, which is mediated by the recovery of salt-induced NO production mechani sm.