Evaluation of dynamic changes of nitric oxide and oxidative stress in hemodialysis patients

测量氧化LDL和ADMA的血浆浓度，这两者都是氧化应激的标志物。OxyLDL明显高于健康组，且经血液透析（HD）进一步升高。HD前ADMA水平高于健康组，随着HD时间的延长，ADMA水平逐渐下降。两组血浆BH_4水平均降低，血浆ADMA水平均升高，心肌DDAH（ADMA水解酶）活性均降低。对照组大鼠心、肾、肝组织中的超氧化物生成量无明显差异，而高血压组大鼠心、肾、肝组织中的超氧化物生成量明显减少。L-精氨酸/ADMA比值与NO生成率呈良好的线性相关。BH_4/BH_2与系统NO生成速率的关系也基本相同。从临床的角度来看，这些参数的变化将显着影响血液透析过程中NO的产生，因此，这些因素的控制和其他方法应进一步研究。

Plasma concentrations of oxidized LDL and ADMA, both of which are markers of oxidative stress were measured. OxyLDL was significantly higher than healthy group and increased further by hemodialysis (HD). ADMA level was higher than healthy group before HD and gradually decreased in the time course of HD.Next, we evaluated the plasma levels of NO-related factors in pathophysiological model rats (hypertension and diabetes mellitus). In both groups, plasma BH_4 level decreased, plasma ADMA level increased, and myocardial DDAH (ADMA hydrolase) activity decreased. Superoxide production of control rats did not differ among heart, kidney and liver, while it decreased significantly in those organs of hypertensive rats.Systemic NO production rate in HD patients was estimated and the rate during HD was significantly higher than in the inter-HD period. There was a good linear correlation between L-arginine/ADMA and systemic NO production rate. Also the same between BH_4/BH_2 and systemic NO production rate. From a clinical viewpoint, variations of these parameters would affect significantly the NO production during HD, and thus control of these factors and other methods should be investigated further.