Erythropoietin (Epo) production during acute inflammation induced by s
.c. turpentine administration in experimental Long-Evans rats increase
d in response to reduced erythropoiesis. A close correlation was found
between decreased haematocrit (Hct) and increased levels of tumour ne
crosis factor-alpha (TNF alpha) in this experimental system. The Epo r
esponse was not different between rats with acute inflammation and ana
emia and control animals with a comparable degree of anaemia. It is co
ncluded that Epo is not an acute phase reactant, and that the Epo resp
onse in acute experimental inflammation in rats is explained by the as
sociated development of anaemia.