RESUMEN
<p><b>OBJECTIVE</b>To study the effect of Xiangdan injection (XDI) in inducing adult SD rat marrow mesenchymal stem cells (rMSCs) orientedly differentiated into neuron-like cells, its characteristics and influencing factors were explored.</p><p><b>METHODS</b>The 5th generation of rMSCs cultured in vitro were pre-treated for 24 hrs by adding basic fibroblast growth factors (bFGF) into the medium, then the inducing liquid was replaced by XDI with different concentration to compare the rMSCs differentiation rate under different constitution of medium, different concentration of inducer and cell density of incubation. The induced cell survival rate under effects of above-mentioned factors was evaluated by trypan blue stain and MTT method.</p><p><b>RESULTS</b>XDI in 1% - 5% concentration could induce rMSCs differentiated into neuron-like cells, the inducing rate reached 83.5 +/- 3.8% 6 - 12 hrs later, more than 90% cells, survival rate was over 36 hrs. The maximal inducing rate and cell survival rate could be obtained by treated with 3 % - 5% XDI, serum-free D/F12 + N2 + bFGF and with the cell density in 2.5 x 10(4)/cm2, when the other factors were the same.</p><p><b>CONCLUSION</b>XDI of 3% - 5% concentration, serum-free D/ F12 + N2 + bFGF (10 microg/L) and with the cell density incubated of 2.5 x 10(4)/cm2 is the optimal condition for oriented induction of rMSCs differentiating to neuron-like cells.</p>