Okano M, Ohnota H, Sasaki R
Department of Food Science and Technology, Faculty of Agriculture, Kyoto University, Japan.
J Nutr. 1992 Jul;122(7):1376-83. doi: 10.1093/jn/122.7.1376.
Erythropoietin (EPO), a glycoprotein produced mainly by the kidney, is the major physiological regulator of erythropoiesis. We developed a sensitive and rapid ELISA for measurement of rat serum EPO with two monoclonal antibodies that recognize different epitopes. To understand the mechanism by which erythropoiesis is impaired in rats deficient in dietary protein, we investigated the levels of the immunoreactive EPO (iEPO) in serums and erythroid precursor cells in hemopoietic tissues during protein deprivation. The iEPO level of 32-d-old rats fed a protein-free diet was lowered to one-third that of rats fed 20% casein at 6 h after protein deprivation began. Protein deprivation decreased the number of EPO-responsive cells in spleen. These results indicate that the impairment of erythropoiesis during protein deficiency is caused by the decrease in serum EPO and the subsequent reduction of the population size of erythroid precursor cells in spleen.
促红细胞生成素（EPO）是一种主要由肾脏产生的糖蛋白，是红细胞生成的主要生理调节因子。我们利用两种识别不同表位的单克隆抗体，开发了一种灵敏快速的ELISA法来检测大鼠血清EPO。为了解蛋白质缺乏大鼠红细胞生成受损的机制，我们研究了蛋白质缺乏期间造血组织中血清和红系前体细胞中免疫反应性EPO（iEPO）的水平。在开始蛋白质缺乏6小时后，喂食无蛋白饮食的32日龄大鼠的iEPO水平降至喂食20%酪蛋白大鼠的三分之一。蛋白质缺乏减少了脾脏中对EPO有反应的细胞数量。这些结果表明，蛋白质缺乏期间红细胞生成受损是由血清EPO减少以及随后脾脏中红系前体细胞数量减少所致。
