Erythropoiesis and erythropoietin synthesis during aseptic acute inflammation.

Erythropoietin (Epo) production during acute inflammation induced by s. c. turpentine administration in experimental Long-Evans rats increased in response to reduced erythropoiesis. A close correlation was found between decreased haematocrit (Hct) and increased levels of tumour necrosis factor-alpha (TNF alpha) in this experimental system. The Epo response was not different between rats with acute inflammation and anaemia and control animals with a comparable degree of anaemia. It is concluded that Epo is not an acute phase reactant, and that the Epo response in acute experimental inflammation in rats is explained by the associated development of anaemia.