Neurogenesis and gliogenesis in the postischemic brain.

LIU J.; BERNABEU, R.; SHARP FR

The Neuroscientist

SAGE

Año: 2000 vol. 6 p. 362 - 370

1089-4098

Stem cells are found throughout the adult mammalian brain, including the subventricular zone (SVZ) adjacentto the lateral ventricles, and in the hippocampal dentate subgranular zone (SGZ). Cells born in theSVZ migrate to the olfactory bulb. Those born in the SGZ migrate into the granule cell layer. Following 5 or10 min of global ischemia in the adult gerbil, there is a tenfold increase in the birth of new cells in the SGZas assessed using bromo-deoxy-uridine incorporation. This begins at 7 days, peaks at 11 days, anddecreases thereafter. Over the ensuing month, approximately one-fourth of the newborn cells disappear. Ofthe remaining cells, 60% migrate into the granule cell layer where two-thirds of these become NeuN,calbindin, and MAP-2 immunostained neurons. The remaining 40% of the cells migrate into the dentatehilus where one-fourth of these become glial fibrillary acidic protein–labeled astrocytes. Death of CA1pyramidal neurons does not stimulate neurogenesis because ischemia-induced tolerance—which does notproduce CA1 injury—also stimulated cell proliferation. It is proposed that ischemia-induced neurogenesiscontributes to the recovery of function, specifically of anterograde and retrograde recent memory functionthat is lost following global ischemia in man.