Objectives To investigate the change of asymmetric NG, NG-dimethyl-L-arginine (ADMA) and elucidate the possible mechanism of endothelial dysfunction in patients with unstable angina.

Methods Screening 103 unstable angina patients hospitalised in our hospital from June 2010 to Jury 2012, the diagnosed standards of unstable angina are typical angina pectoris, positive ECG or exercise stress test and with more than 70% stenosis of single or multiple coronary arteries by angiography, excluded other diseases, such as hypertension, diabetes, hypertrophic cardiomyopathy et al. We selected 20 normal persons with matching age and sex as control. The levels of ADMA, NO, ET-1, SOD, MDA, blood lipid, blood glucose, blood viscosity, fibrinogen were measured respectively.

Results 1. Compared with control group, the levels of ADMA, ET-1 were significantly increased and the level of NO was significantly decreased in unstable angina group (5.60 ± 1.79 vs 1.01 ± 0.05, 70.96 ± 16.05 vs 50.58 ± 7.52, 52.8 ± 7.59 vs 75.6 ± 18.3, P < 0.05 respectively). ADMA was positive correlated with the ratio of ET-1/NO. The levels of ADMA and ET-1 were also increased significantly in unstable angina group.. There were statistical significance between control and unstable angina group for the levels of SOD and MDA (70.3 ± 17.8 vs 104 ± 18.8 and 6.25 ± 0.79 vs 4.09 ± 0.58, P < 0.05 respectively). The levels of blood lipid (TC, TG, LDL, HDL-C, Lpa) in most patients of CHD were abnormal, and were higher than those in control group (P < 0.05). There were no differences for the levels of blood glucose, blood viscosity, fibrinogen between two groups.

Conclusions This study shows endothelial dysfunction in the patients with unstable angina is associated with the increase of ADMA. Oxide stress may play an important role in unstable angina.