Endogenous neurogenesis can arise from a variety of physiological stimuli including exercise, learning, or "enriched environment" as well as pathological conditions such as ischemia, epilepsy or cortical spreading d...Endogenous neurogenesis can arise from a variety of physiological stimuli including exercise, learning, or "enriched environment" as well as pathological conditions such as ischemia, epilepsy or cortical spreading depression. Whether all these conditions use a common trigger to set off endogenous neurogenesis is yet unclear. We hypothesized that cortical spreading depression(CSD) induces neurogenesis in the cerebral cortex and dentate gyrus after cerebral venous ischemia. Forty-two Wistar rats alternatively underwent sham operation(Sham), induction of ten CSDs or venous ischemia provoked via occlusion of two adjacent superficial cortical vein followed by ten induced CSDs(CSD + 2-VO). As an additional control, 15 na?ve rats received no intervention except 5-bromo-2′-deoxyuridine(Brd U) treatment for 7 days. Sagittal brain slices(40 μm thick) were co-stained for Brd U and doublecortin(DCX; new immature neuronal cells) on day 9 or Neu N(new mature neuronal cells) on day 28. On day 9 after sham operation, cell proliferation and neurogenesis occurred in the cortex in rats. The sole induction of CSD had no effect. But on days 9 and 28, more proliferating cells and newly formed neurons in the ipsilateral cortex were observed in rats subjected to CSD + 2VO than in rats subjected to sham operation. On days 9 and 28, cell proliferation and neurogenesis in the ipsilateral dentate gyrus was increased in sham-operated rats than in na?ve rats. Our data supports the hypothesis that induced cortical neurogenesis after CSD + 2-VO is a direct effect of ischemia, rather than of CSD alone.展开更多
基金supported by a grant from Johannes Gutenberg-University
文摘Endogenous neurogenesis can arise from a variety of physiological stimuli including exercise, learning, or "enriched environment" as well as pathological conditions such as ischemia, epilepsy or cortical spreading depression. Whether all these conditions use a common trigger to set off endogenous neurogenesis is yet unclear. We hypothesized that cortical spreading depression(CSD) induces neurogenesis in the cerebral cortex and dentate gyrus after cerebral venous ischemia. Forty-two Wistar rats alternatively underwent sham operation(Sham), induction of ten CSDs or venous ischemia provoked via occlusion of two adjacent superficial cortical vein followed by ten induced CSDs(CSD + 2-VO). As an additional control, 15 na?ve rats received no intervention except 5-bromo-2′-deoxyuridine(Brd U) treatment for 7 days. Sagittal brain slices(40 μm thick) were co-stained for Brd U and doublecortin(DCX; new immature neuronal cells) on day 9 or Neu N(new mature neuronal cells) on day 28. On day 9 after sham operation, cell proliferation and neurogenesis occurred in the cortex in rats. The sole induction of CSD had no effect. But on days 9 and 28, more proliferating cells and newly formed neurons in the ipsilateral cortex were observed in rats subjected to CSD + 2VO than in rats subjected to sham operation. On days 9 and 28, cell proliferation and neurogenesis in the ipsilateral dentate gyrus was increased in sham-operated rats than in na?ve rats. Our data supports the hypothesis that induced cortical neurogenesis after CSD + 2-VO is a direct effect of ischemia, rather than of CSD alone.