The inadequate erythropoiesis was characterized in a set of other experiments conducted in these rats (Cunha et al. 2014), where the authors demonstrated that vitamin A deficiency down-regulated renal Epo mRNA and up-regulated Hmox1 in the spleen, suggesting an increased phagocytosis of malformed or undifferentiated erythrocytes and consequent iron accumulation in the spleen, in the heme form. Here, EPO is linked to vitamin A deficiency.