Abstract
Prepubertal hypopituitary dwarfs are anemic and have reduced levels of erythropoietin-stimulating factor (ESF) in the urine. Treatment with human growth hormone (HGH) in doses sufficient to produce linear growth and weight gain induces bone marrow lymphocytosis, increased erythropoiesis indicated by an increase of the red cell mass (RCM) and improved iron kinetic studies. This was associated with increased concentrations of ESF in the urine, increased transferrin levels, and expansion of the plasma volume. The combination of testosterone and HGH increased further erythropoiesis but could not be specifically ascribed to testosterone, since the continued action of HGH could be responsible for the observed effects. The excretion of ESF was not increased further. Testosterone did, however, maintain ESF excretion on deletion of HGH from the regimen, suggesting at least one common mode of action for these hormones in the hypoanabolic subject. In contrast, testosterone failed to maintain the plasma volume increase induced by HGH and did not further effect the observed bone marrow lymphocytosis.
