EFFECT OF IRON ON ERYTHROPOIETIN PRODUCTION IN ANEMIC PIGLETS

In the present study the response of plasma erythropoietin to iron inj ection in anaemic piglets was examined. At the age of 16 days, 4 pigle ts from the same litter were given 180 mg iron subcutaneously. After i ron injection, blood samples for estimation of erythropoietin activity in plasma, haemoglobin concentration, and reticulocyte counts were ta ken every 6 or 12 h for 31/2 days. Plasma erythropoietin activity was estimated by a monoclonal enzyme-immunoassay (ELISA), developed for hu man erythropoietin. On the day of iron injection, haemoglobin concentr ation ranged between 41 and 48 g/l, reticulocyte counts from 9 to 17 p ercent, and plasma erythropoietin between 22 and 144 mU/ml. In 3 of th e 4 piglets, iron injection resulted in a 2-6 fold increase in erythro poietin activity. Maximal erythropoietin activities were observed 24-4 2 h after injection, and after 66 h, the activities were close to the pretreatment values. It is concluded that in our experiment, iron, per se, has stimulated erythropoietin production.