Niwa T, Takeda N, Yoshizumi H
Nagoya University Daiko Medical Center, Japan.
Kidney Int. 1998 Jun;53(6):1801-6. doi: 10.1046/j.1523-1755.1998.00944.x.
To determine the metabolism of ribonucleic acid (RNA) in uremia, serum and urine levels of ribonucleosides in uremic patients were analyzed using reversed-phase high-performance liquid chromatography. The serum levels of xanthosine and all modified ribonucleosides were increased in undialyzed patients with chronic renal failure (CRF), and patients undergoing hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD). The serum level of pseudouridine was markedly increased in all the uremic patients especially CAPD patients (32 times higher than normal). By contrast, the serum level of adenosine did not show any significant change in the uremic patients. Interestingly, the serum and urine levels of inosine were significantly decreased in all the uremic patients, suggesting that the production of inosine is decreased in uremic patients. The serum level of uridine was significantly elevated only in the HD patients. The serum levels of all ribonucleosides except inosine and uridine decreased significantly after HD. The urinary excretion of inosine, 1-methyladenosine, 1-methylguanosine, N2,N2-dimethylguanosine and N4-acetylcytidine was significantly decreased in the CRF patients, leading to the accumulation of these modified ribonucleosides in the uremic serum. CAPD patients showed markedly increased serum levels of modified ribonucleosides such as pseudouridine, 1-methylinosine, and N2,N2-dimethylguanosine and N4-acetylcytidine as compared with the HD patients. These results demonstrate that there was an altered metabolism of RNA in uremic patients with marked accumulation of modified ribonucleosides.
为了确定尿毒症患者体内核糖核酸（RNA）的代谢情况，采用反相高效液相色谱法分析了尿毒症患者血清和尿液中核糖核苷的水平。慢性肾衰竭（CRF）未透析患者、接受血液透析（HD）和持续性非卧床腹膜透析（CAPD）的患者，其血清中黄嘌呤核苷及所有修饰核糖核苷的水平均升高。所有尿毒症患者，尤其是CAPD患者，其假尿苷的血清水平显著升高（比正常水平高32倍）。相比之下，尿毒症患者血清中腺苷水平无显著变化。有趣的是，所有尿毒症患者血清和尿液中次黄苷水平均显著降低，提示尿毒症患者次黄苷生成减少。仅HD患者的尿苷血清水平显著升高。HD后，除次黄苷和尿苷外，所有核糖核苷的血清水平均显著降低。CRF患者尿液中次黄苷、1-甲基腺苷、1-甲基鸟苷、N2,N2-二甲基鸟苷和N4-乙酰胞苷的排泄显著减少，导致这些修饰核糖核苷在尿毒症血清中蓄积。与HD患者相比，CAPD患者血清中修饰核糖核苷如假尿苷、1-甲基次黄苷、N2,N2-二甲基鸟苷和N4-乙酰胞苷的水平显著升高。这些结果表明，尿毒症患者存在RNA代谢改变，且修饰核糖核苷明显蓄积。
