The (Real) Neurogenic/Gliogenic Potential of the Postnatal and Adult Brain Parenchyma

Figure 1

Heterogeneity of cell genesis (neurogliogenesis) in the mammalian CNS. Schematic summary of the features and location of different neurogenic and gliogenic processes occurring spontaneously in the postnatal and adult CNS. Red dots indicate newlyborn cells. SVZ: subventricular zone; SGZ: subgranular zone; EGL: external germinal layer; SPL: subpial layer (rabbit); PSA: PSA-NCAM; P23: postnatal day 23. Question marks indicate lack of knowledge about the origin, late differentiative steps, and final integration of newly generated parenchymal neurons. Photographs: top left, cluster, and chain of neuroblasts in the adult rabbit striatum (courtesy of Paola Crociara); top right, newly generated neurons in the adult rabbit cerebellar cortex (modified from Ponti et al., [19]); middle, modified from Ponti et al., [35]; bottom, Ng2+ polydendrocyte and multipolar Map5+ cell in the adult mouse and rabbit, respectively, (courtesy of Paola Crociara).