Studies on the Role of the Kidney in Erythropoiesis 1. An experimental Study on the Role of the Kidney in Erythropoiesis in Uremic Rabbits Using Radioacitve Iron(Fe59)

Choo, Kun Weon; Hurh, Yong; Kim, Han Jin

Abstract

The relationship between the kidney and erythropoiesis was investigated. Thirty-three rabbits were used of which nine rabbits were subjected to bilateral nephrectomy, eight to unilateral nephrectomy with ureter ligation of the oppositekidney and nine to bilateral ureter ligation. The controls consisted of four rabbits. In each group, N.P.N., B.U.N., creatinine, normoblast count and half time of plasma iron disappearance(Fe59) were measured 72 hours after the operation and the following data were obtained. Normal group:N.P.N.,27.9mg%(18.5-36.0mg%), B.U.N.,17.2mg%(9.9-30.4mg%), creatinine, 1.3mg%(0.7-1.62mg%)normoblast, 28%(13-36%) and half time of plasma iron disappearance, 62min(40-92min) Bilaterally nephrectomized group: N.P.N.,262.1mg%(198.0-267.3mg%), B.U.N.,141.2mg%(130.5-146.0mg%), creatinine, 19.1mg%(9.45-19.47mg%) ,normoblast ,22% (1.0-5.0%)and half time of plasma iron disappearance, 139.8min(87-196min) Uinlateral nephrectomized group with ureter ligation of the opposite kidney: N.P.N.,256.2mg%(199.8-420.0mg%), B.U.N.,108.0mg%(90.0-112.5mg%) ,creatinine, 17.4mg%(12.4-18.7mg%),normoblast, 14.2% (8.0-26.0%) and half time of plasma irondisappearance, 86.0min(51.0-159.0min) Bilaterally ureter ligated group: N.P.N.,242.7mg%(236.4-333.0mg%), B.U.N.,135.5mg% (129.0-151.3mg%) ,creatinine, 19.8mg%(18.9-21.3mg%), normoblast, 18.2% (13.0-20.0%) and half time of plasma iron disappearance, 69.5min(49.0-92.0min) Normoblast markedly decreased(to 2.2%) and half time of plasma iron disappearance(Fe59) was strikingly higher(87 to 196 min., mean 139,8min.)than normal rabbits(40 to 92 min., mean 62 min.) in bilateral nephrectomized group. This marked depression of erythropoiesis occurred in bilateral nephrectomized group while in the group of bilateral ureterligation and unilateral nephrectomy with ureter ligation of opposite kidney only moderate depression of erythropoiesis was noted despite the elevation in azotemia and the degree of malnutrition were almost same level in these three groups. It suggests that the kidney is probably the source of and erythropoietic factor.