Objective To investigate proliferation and differentiation of neural stem cells in adult rats after cerebral infarction. Methods Models of cerebral infarction in rats were made and the time-course expression of bromodeoxyuridine（BrdU）

Musashi1

glial fibrillary acidic protein （GFAP）

and neuronal nuclear antigen （NeuN） were determined by immunohistochemistry and immunofluorescence staining. BrdU and Musashi1 were used to mark dividing neural stem cells. GFAP and NeuN were used to mark differentiating neural stem cells. Results Compared with controls

the number of BrdU-labeled and BrdU-labeled with Musashi1-positive cells incre-ased strikingly 1 day after cerebral infarction; approximately 6 fold with a peak 7 days later; markedly decreased 14 days later

but was still elevated compared with that of controls; decling to the control level 28 days later. The number of BrdU-labeled with GFAP-positive cells nearly remained unchanged in the hippocampus after cerebral infarction. The nu-mber of BrdU-labeled with NeuN-positive cells increased strikingly 14 days after cerebral infarction

reached maximum peak in the hippocampus 28 days after cerebral infarction in rats. Conclusion Cerebral infarction stimulate proliferation of inherent neural stem cells and most proliferated neural stem cells differentiate into neurons.