title: Temporal variation of induction neurogenesis in a rat model of transient middle cerebral artery occlusion.
abstract: OBJECTIVE
  The adult brain is capable of neurogenesis after cerebral ischemia. We investigated the presence of new neural precursors after transient middle cerebral artery ischemia adult rats.
  
  
  METHODS
  Transient middle cerebral artery ischemia was induced in adult Wistar rats (n=13) using the monofilament method. In the experimental group (n=8), animals were harvested at days 3, 7, 10, 17 and 21 after ischemia. Five animals served as controls. Sagittal sections through the ischemic cortex were double-stained for neural (nestin and beta-tubulin, nestin and PCNA), glial (nestin and GFAP) and oligodendroglial (nestin and O4, CNP and PCNA) precursors. Double-stained cells were also counted under high-power view and tabulated over time.
  
  
  RESULTS
  In the subventricular zone (SVZ), there was positive double-staining starting at day 3 showing proliferating astrocytic precursors (nestin + GFAP, 5-20% of cells), neuronal stem cells (nestin + PCNA, 95% of cells) and neuronal precursors (nestin + beta-tubulin, 50% of cells). Within the penumbra, a more robust response showed more astrocytic precursors (50-80% of cells), premature and differentiated oligodendrocytes, neuronal stem cells (85% of cells) and neuronal precursors (15% of cells). In the area of the stroke, there was an intermediate response consisting of more astrocytic precursors (10-20% of cells), premature oligodendrocytes (45-100% of cells), neuronal stem cells (95% of cells) and neuronal precursors (25% of cells). Results were confirmed with cell counting analysis.
  
  
  CONCLUSIONS
  Our results show that not only do neural precursors proliferate in the SVZ, there is definite and real response in the penumbra and ischemic cortex, suggesting the ability of repair in the central nervous system.
authors.affiliation: Department of Neurosurgery, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York 10467, USA. jma@nsny.com
authors.forename: John M
authors.initials: JM
authors.lastname: Abrahams
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Lenart
authors.forename: Michael E
authors.initials: ME
authors.lastname: Tobias
mesh_terms: D053687:Adult Stem Cells / Q000378:metabolism; D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D002545:Brain Ischemia / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology*; D007150:Immunohistochemistry; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D055495:Neurogenesis / Q000502:physiology*; D009474:Neurons / Q000378:metabolism; D009836:Oligodendroglia / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors