[The effect of GH on erythropoiesis in vivo].

It has been demonstrated that the direct and/or indirect stimulation of hematopoiesis is one of the effects of the growth hormone (GH) in vitro. In order to study the effect of GH on erythropoiesis in vivo, the variation of hemochrome in a group of 8 subjects with GH deficiency (GHD) were monitored during a substitutive therapy with biosynthetic GH (rhGH) at dose of 0.4 U/kg/week. Hemoglobin (Hb), hematocrit (Ht), mean corpuscular volume (MCV), number of red blood cells (RBC) were analysed in all subjects at the beginning and after 9 months of treatment. The effectiveness of therapy was demonstrated by statistically significant variations in height, height SDS, growth velocity, serum levels of IGF-I. After 9 months of rhGH therapy, a significant increase was observed in all values considered with exception of MCV. In conclusion Gh would appear to stimulate erythropoiesis, directly or indirectly, and these results would appear to indicate an in vivo confirmation.