Objective: To investigate whether there is endogenous neural stem cell proliferation and whether these proliferated neural stem cells represent neural plasticity in the adult rats after cerebral infarction.
Methods: Cerebral infarction models of rats were established and the dynamic expression of bromodeoxyuridine (BrdU), BrdU/polysialylated neural cell adhesion molecule (PSA-NCAM) were determined by immunohistochemistry and immunofluorescence staining. BrdU was used to mark dividing neural stem cells. PSA-NCAM was used to mark the plasticity of neural stem cells.
Results: Compared with controls, the number of BrdU-positive cells in the subventricular zone (SVZ) and hippocampus increased significantly at 1st day after cerebral infarction (P < 0.05), reached maximum at 7th day, decreased markedly at 14th day, but it was still elevated compared with that of the controls (P < 0.05). The number of BrdU-labeled with PSA-NCAM-positive cells increased significantly at 7th day (P < 0.05), reached maximum at 14th day, markedly decreased at 28th day, but it was still elevated compared with that of the controls (P < 0.05). It was equal to 60% of the number of BrdU-positive cells in the same period.
Conclusion: Cerebral infarction may stimulate the proliferation of endogenous neural stem cells in situ and most proliferated neural stem cells represent neural plasticity.