[Hyperparathyroidism and anemia: experimental study in the rat (author's transl)].

Red blood cell (RBC) production has been explored in hyperparathyroid as compared to normal rats. The hyperparathyroid state was obtained by feeding the rats a calcium-deficient diet during 30 days. A significant decrease (p less than 0.001) in reticulocyte count and in erythrocyte 59Fe incorporation was observed in hyperparathyroid rats when compared to control animals. A comparable inhibition of erythrocyte 59Fe incorporation in hyperparathyroid rats was found when the study was performed after stimulating bone marrow activity by acute arterial hemorrhage. These results of decreased RBC production using a model of endogenous hyperparathyroidism could be confirmed in additional experiments using a model of exogenous hyperparathyroidism. In this model, the rats received either parathyroid extract (3 x 10 USP/day during 8 days) or vehicle only. Again, a decrease in erythrocyte 59Fe incorporation was observed in hyperparathyroid animals when compared to control animals. It is concluded that the hyperparathyroid state is accompanied by a decrease of RBC production in the rat. It is probable that a similar pathogenesis underlies the anemia of patients with primary or secondary hyperparathyroidism.