Objective   To investigate the effect of endothelial progenitor cells (EPCs) which complexed with neuron stem cells (NSCs) after transplanted into ischemia and reperfusion (I/R) rat model on the proliferation and apoptosis of the NSCs and vasal construction.    Methods   Totally 150 SD adult male rats were randomly and equally divided into 5 groups

shamoperation group

I/R group

I/R+NSCs group

I/R+EPCs group

and I/R+NSCs+EPCs group. The rats were further divided into 5 subgroups according to the time points of 3

7

14

30 and 60 d after transplantation. I/R rat model was established by reversiblyligating middle cerebral artery occlusion. NSCs were derived from the hippocampus of SD rats born in 24 h and identified with Nestin staining. EPCs were obtained from the artery blood of SD rats and verified with immunocytochemical stainings of CD31

CD34 and KDR after culture. The complex of NSCs and EPCs was produced with aid of laminin. Then the complex were transplanted into the ischemia penumbra of corresponding model rat brain. The proliferation and apoptosis of NSCs

and the fomation of new vessels were observed through immunohistochemistry and doublelabeled immunofluorescence staining.    Results   The proliferation of NSCs was increased

apoptosis cells were decreased and the new vessels were raised in the complex transplantation when compared with single NSCs or EPCs transplantation groups.    Conclusion   The complex of NSCs and EPCs transplantation improves the proliferation of NSCs

suppresses cell apoptosis and promotes the formation of new vessels.