Presence of Toxic Substances Which Inhibit Erythro-poiesis in Serum of Uremic Nephrectomized Rabbits

Abstract

The presence of toxic substances which inhibit erythropoiesis in uremic sera is still undetermined. We examined the effect of aceton-methylalcohol extracts of serum of nephrectomized rabbits with uremia on the erythropoiesis.
The percentage red cell iron utilization was markedly reduced in nephrecto-mized rabbits with uremia. The administration of aceton-methylalcohol extracts of uremic rabbit serum resulted in a marked decrease of percentage red cell iron utilization in rats which fasted for 32 hours. However, the administration of aceton-methylalcohol extracts of normal rabbit serum did not result in any decrease of percentage red cell iron utilization in fasting rats. The administra-tion of uremic extracts caused a marked shortening of the reticulocyte life span in colehicinized rats. The percentage of erythroblasts labeled with H³-thymidine in vitro was markedly reduced in uremic nephrectomized rabbits. The administration of uremic extracts resulted in a decrease of the in vivo incorporation of H³-thymidine in erythroblasts with their increased abortion in rats which starved for 32 hours.
These results demonstrate the presence of toxic substances which inhibit erythropoiesis in uremic rabbit serum.