['To detect the effect of recombinant human growth hormone (rhGH) to mesenchymal stem cells (MSCs) in vitro.', 'Various concentrations of rhGH (terminal concentrations 1, 10, 50, 100, 200 and 500 microg/L) were added to medium containing the second generation of MSCs, A value was measured by MTT method at various concentrations and at 24, 48 and 72 h. The expression of insulin-like growth factor 1(IGF-1) mRNA in the presence (24, 48 and 72 h) or absence (the 4(th) day, the 9(th) day, the 10(th) day, the 2(nd) week, the 3(rd) week and the 4(th) week post removal of rhGH) of various rhGH concentrations was determined by RT-PCR.', 'rhGH could promote the MSCs growth at concentration > 10 microg/L in a time-dependent manner. The optimal concentration was 200 microg/L with a growth rate 144.74%. The expression of IGF-1 mRNA increased in a time-dependent manner gradually (0.6749 +/- 0.0084, 0.7781 +/- 0.0068, 0.8230 +/- 0.0060 at 24, 48 and 72 h, respectively at 200 microg/L rhGH). After rhGH withdraw, the expression of IGF-1 mRNA decreased in a time-dependent manner till 2 weeks (0.5287 +/- 0.0077, 0.5747 +/- 0.0050, 0.6068 +/- 0.0056, 0.7071 +/- 0.0089, 0.5791 +/- 0.0057, 0.5781 +/- 0.0081 at the 4(th) day, the 9(th) day, the 10(th) day, the 2(nd) week, the 3(rd) week and the 4(th) week post removal of rhGH).'] Does [ Recombinant human growth hormone promote in vitro mesenchymal stem cell growth ]?