Influence of Several Hormones on Erythropoiesis and Oxygen Consumption in the Hypophysectomized Rat

Adrenocorticotrophic hormone (ACTH), thyroid stimulating hormone (TSH), adrenocortical extract (ACE), hydrocortisone (F), corticosterone (B), 11-dehydrocorticosterone and 3,5,3'-triiodothyronine (T-3) induced a moderate to marked erythropoietic effect in the hypophysectomized rat as indicated by an increase in both Fe⁵⁹ incorporation in RBC and total circulating red cell volume. A corresponding increase in oxygen consumption was also observed. Angiotensin increased red cell volume and radioactive iron incorporation in RBC of hypophysectomized rats and stimulated Fe⁵⁹ incorporation in hypophysectomized-adrenalectomized rats, but did not exert a significant effect on oxygen consumption. Cobalt injections resulted in a significant increase in red cell volume and Fe⁵⁹ incorporation in RBC of hypophysectomized rats, but produced a significant decrease in oxygen consumption. The significance of these findings is discussed.