Relationship between salt intake,nitric oxide and asymmetric dimethylarginine and its relevance to patients with end-stage renal disease

Patients with essential hypertension (n = 24) were administered a low-salt diet (2 g NaCl/day), a high-salt diet (20-23 g) and then a low-salt diet for 7 days, and plasma levels of nitrate and nitrite (NOx) and asymmetric dimethylarginine (ADMA) were examined. There was a negative correlation between the percent changes in mean blood pressure and the plasma NOx concentration after salt loading and restriction. The percent change in plasma ADMA concentration was negatively correlated with that in the plasma NOx concentration after salt loading and restriction. In patients with end-stage renal disease (n = 51), the plasma ADMA concentration was positively correlated with the duration of dialysis treatment. The frequency of cardiovascular events was greater in patients with a plasma ADMA level of >/=3 microM than in those with a plasma AMDA level of <3 microM. The results indicate that ADMA is not only a modulator of salt sensitivity in hypertension but also a cardiovascular risk factor in end-stage renal disease.