Erythropoietin: biological aspects and clinical usefulness.

In the eighties there has been an enormous increase in our knowledge about erythropoietin, previously defined as "an elusive hormone". In this review we summarize the structural and molecular features, the mechanisms of production and of metabolism, the more important methods of assay, the mechanism of action and the biological effects, the main pathophysiological aspects and the therapeutic usefulness of the hormone.