INFLUENCE OF GROWTH-RATE ON THE ABILITY OF HYPER-TRANSFUSION INDUCED PLETHORA TO SUPPRESS ERYTHROPOIESIS IN THE GROWING-RAT

  • 1 January 1981
    • journal article
    • research article
    • Vol. 9  (3) , 209-213
Abstract
To induce different rates of growth male rats 23 days of age were placed on diets containing on protein or 20% casein for 10 days. They were divided into 3 subgroups which were placed on diets containing 5, 10 or 20% casein until the end of the experimental period (day 17). Adult rats were used as controls. Rats were hypertransfused on days 8 and 9 and RBC-59Fe uptake determined on day 17. Body weight was directly correlated with the casein content of the diet in the growing rats. RBC-radioiron incorporation was influenced by the protein content of the diet in the young rats in spite of the fact that hematocrits were over 60% in all the animals. 59Fe uptake by erythrocytes was unrelated to diet composition in the adult rats. When radioiron incorporation values were plotted against growth rate, it became evident that a close direct correlation exists between erythropoiesis and growth rate in transfused-polycythemic rats, indicating that the degree of suppression of red cell production provoked by hypertransfusion-induced plethora is dependent on the rate of growth of the animal, keeping with it an inverse relationship.