Division of Nephrology, Department of Internal Medicine, University Medical Center Groningen, Groningen, The Netherlands.
Nephrol Dial Transplant. 2010 Oct;25(10):3256-60. doi: 10.1093/ndt/gfq149. Epub 2010 Mar 25.
Renin-angiotensin-aldosterone system (RAAS) blockade improves prognosis in renal patients, but usually requires diuretic co-treatment. RAAS blockade can decrease erythropoietin (EPO) and/or haemoglobin (Hb) levels. Diuretics decrease EPO in rodents, but their effect on EPO and Hb in humans is unknown.
Proteinuric renal patients with preserved renal function were treated during 6-week periods with placebo, losartan 100 mg/day (LOS) and LOS plus hydrochlorothiazide 25 mg/day (LOS/HCT), in random order.
Hb was inversely related to proteinuria, and EPO levels were inappropriately low in relation to Hb. Hb was lowered by LOS with and without HCT. EPO was decreased by LOS/HCT, but not by LOS.
EPO and Hb are reduced by HCT added to LOS in proteinuric renal patients with preserved renal function. We hypothesize that EPO reduction by HCT is caused by a decrease in renal oxygen requirement, which is the main stimulus for EPO production, due to the inhibition of active tubular sodium reabsorption. Further studies should explore the exact mechanism of this phenomenon and its clinical impact.
肾素-血管紧张素-醛固酮系统（RAAS）阻断剂可改善肾功能患者的预后，但通常需要联合利尿剂治疗。RAAS 阻断剂可降低促红细胞生成素（EPO）和/或血红蛋白（Hb）水平。利尿剂可降低啮齿动物的 EPO，但它们对人类 EPO 和 Hb 的影响尚不清楚。
在 6 周的时间内，采用随机顺序，分别用安慰剂、氯沙坦 100mg/天（LOS）和氯沙坦加氢氯噻嗪 25mg/天（LOS/HCT）治疗肾功能正常的蛋白尿患者。
Hb 与蛋白尿呈负相关，而 EPO 水平与 Hb 不成比例地降低。LOS 加或不加 HCT 均可降低 Hb。LOS/HCT 降低 EPO，但 LOS 则没有。
在肾功能正常的蛋白尿患者中，HCT 加用 LOS 可降低 EPO 和 Hb。我们假设 HCT 降低 EPO 是由于主动肾小管钠重吸收抑制导致肾脏氧需求减少，而肾脏氧需求减少是 EPO 产生的主要刺激因素。进一步的研究应该探讨这种现象的确切机制及其临床影响。
