[Changes of serum asymmetric dimethylarginine in essential hypertension before and after the treatment]

To investigate the relationship between serum asymmetric dimethylarginine (ADMA) and blood pressure as well as target organ damage in essential hypertension, and to evaluate the effects of enalapril and losartan on them.

Forty-two newly diagnoszed patients with essential hypertension were randomly divided into enalapril-treated group and losartan-treated group. Serum ADMA, L-arginine, and nitric oxide( NO) were measured before and after the treatment for 8 weeks. Twenty-three healthy volunteers were included as control subjects.

The concentrations of ADMA and L-arginine in serum were significantly higher but the level of nitric oxide was relatively lower ( P < 0.01 ) in hypertensive patients than those in control subjects. Serum ADMA was higher in different levels of blood pressure and target organ damage. Treatment with enalapril or losartan for 8 weeks not only reduced blood pressure but also decreased serum ADMA (P <0.01 ). Furthermore, treatment with these drugs also increased the level of serum nitric oxide but didn't change the level of L-arginine.

The concentrations of serum ADMA and L-arginine were increased, but the level of nitric oxide was decreased in the early stage of essential hypertension. Both enalapril and losartan could ameliorate the endothelial function by reducing the concentration of ADMA.