Tomson C R, Channon S M, Parkinson I S, McArdle P, Qureshi M, Ward M K, Laker M F
Department of Medicine, University of Newcastle upon Tyne, UK.
Clin Chim Acta. 1989 Apr 14;180(3):255-64. doi: 10.1016/0009-8981(89)90007-7.
Whole blood ascorbate, plasma oxalate, serum cholesterol, and capillary fragility were measured at monthly intervals for 3 mth in 7 patients receiving continuous ambulatory peritoneal dialysis and 4 receiving haemodialysis, to whom ascorbate supplements had not been prescribed for at least 12 mth. Ascorbate supplements, 25 mg/day, were prescribed for the first month and 50 mg/day for the second month; in the final month patients received no supplements. Whole blood ascorbate was below normal in 6/11 patients at the start of the study but was normal in 10/11 patients when taking ascorbate 50 mg/day. No significant changes in plasma oxalate were observed with these doses of ascorbate, and correction of ascorbate deficiency had no effect on serum cholesterol, mean cell volume, or the results of capillary fragility tests. In a supplementary study, ascorbic acid 500 mg/day was administered for 3 wk to 11 patients. This resulted in a significant rise in mean plasma oxalate from 30.3 (SEM 3.5) to 48.4 (SEM 20.3) mumol/l.
对7例接受持续性非卧床腹膜透析的患者和4例接受血液透析的患者，在至少12个月未补充抗坏血酸的情况下，每隔1个月测量全血抗坏血酸、血浆草酸盐、血清胆固醇和毛细血管脆性，持续3个月。在第一个月给予抗坏血酸补充剂25mg/天，第二个月给予50mg/天；在最后一个月患者不接受补充剂。在研究开始时，11例患者中有6例全血抗坏血酸低于正常水平，但在服用50mg/天抗坏血酸时，11例患者中有10例全血抗坏血酸正常。这些剂量的抗坏血酸未观察到血浆草酸盐有显著变化，抗坏血酸缺乏的纠正对血清胆固醇、平均细胞体积或毛细血管脆性试验结果没有影响。在一项补充研究中，对11例患者给予500mg/天的抗坏血酸，持续3周。这导致平均血浆草酸盐从30.3（标准误3.5）显著升高至48.4（标准误20.3）μmol/L。
