Temporal profile of neural stem cell proliferation in the subventricular zone after ischemia/hypoxia in the neonatal rat brain

Abstract Objectives: Ischemia/hypoxia (I/H) causes severe neonatal brain injury, such as periventricular leukomaracia and hypoxic/ischemic encephalopathy. Neural stem cell research could lead to a treatment for such disorders. In order to elucidate the dynamic changes in neural stem cells in the neonatal brain after I/H, we investigated the proliferation of new cells in the subventricular zone (SVZ). Methods: Seven-day-old Wister rats were subjected to ligation of the left carotid artery followed by 2 hours of hypoxic stress (8% O2 and 92% N2, at 33°C). In order to elucidate the dynamic change of neural stem cells in the SVZ, single bromodeoxyuridine (BrdU; 50 mg/kg) was administered 2 hours before death 1, 7, 14 and 21 days after I/H. Immunohistochemical and immunofluorescent studies for BrdU and doublecortin (DCX) were carried out. As a control, a group of rats was subjected to sham surgery (incision of skin, but no ligation of the carotid artery) and no I/H. Results: The numbers of BrdU-labeled cells i...