Neurogenesis by activation of inherent neural stem cells in the rat hippocampus after cerebral infarction.
OBJECTIVE
To investigate the changes of neural stem cells (NSCs) in the rat hippocampus after cerebral infarction (CI) and to evaluate the neurogenesis caused by the activation of NSCs.


METHODS
CI models of rats were made and rats were assigned to 6 groups: sham-operated, 1 day, 3 days, 7 days, 14 days, and 28 days after CI. The dynamic expression of bromodeoxyuridine (BrdU), polysialylated neural cell adhesion molecule (PSA-NCAM), glial fibrillary acidic protein (GFAP), and neuronal nuclear antigen (NeuN) were determined by immunohistochemistry and immunofluorescence staining. BrdU was used to mark the proliferated NSCs. PSA-NCAM was used to mark the plasticity of activated NSCs. GFAP and NeuN were used to mark the differentiated NSCs.


RESULTS
Compared with the controls, the number of BrdU+ cells in the hippocampus increased significantly at 1 day after CI (P < 0.05), reached peak at 7 days after CI (P < 0.05), decreased but still elevated compared with the controls at 14 days after CI (P < 0.05), and nearly unchanged at 28 days after CI. The number of BrdU+/PSA-NCAM+ cells increased significantly at 7 days after CI (P < 0.05), reached peak at 14 days after CI (P < 0.05), and decreased but still elevated compared with the controls at 28 days after CI (P < 0.05). The number of BrdU+/PSA-NCAM+ cells was equal to 60% of the number of BrdU+ cells in all the same period. The number of BrdU+/NeuN+ cells in the hippocampus increased significantly at 14 days after CI (P < 0.05) and reached peak at 28 day after CI (P < 0.05). The number of BrdU+/GFAP+ cells in the hippocampus nearly unchanged after CI.


CONCLUSIONS
CI can stimulate the proliferation of inherent NSCs, and most proliferated NSCs may differentiate into neurons and represent neural plasticity.
Zhang
Bo
B
Department of Neurosurgery, the First Affiliated Hospital of Dalian Medical University, Dalian 116011, China. zhangbodl@126.com
Wang
Ren-zhi
RZ
Lian
Zhi-gang
ZG
Song
Yang
Y
Yao
Yong
Y
D053687:Adult Stem Cells / Q000166:cytology* / Q000378:metabolism; D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D002467:Cell Nucleus / Q000473:pathology; D002544:Cerebral Infarction / Q000378:metabolism / Q000473:pathology*; D018891:Dentate Gyrus / Q000166:cytology / Q000378:metabolism; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology* / Q000378:metabolism; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism; D039842:Neural Cell Adhesion Molecule L1 / Q000378:metabolism; D055495:Neurogenesis / Q000502:physiology*; D009474:Neurons / Q000166:cytology* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012794:Sialic Acids / Q000378:metabolism
D005904:Glial Fibrillary Acidic Protein; D009419:Nerve Tissue Proteins; D039842:Neural Cell Adhesion Molecule L1; D012794:Sialic Acids; C103469:polysialyl neural cell adhesion molecule; D001973:Bromodeoxyuridine