Subventricular zone

Subventricular zone (SVZ) is a paired brain structure situated throughout the lateral walls of the lateral ventricles. Along with the subgranular zone of dentate gyrus, subventricular zone serves as a source of neural stem cells in the process of adult neurogenesis. It harbors the largest population of proliferating cells in the adult brain of rodents [Altman J. Autoradiographic investigation of cell proliferation in the brains of rats and cats. Anat Rec 145: 573–592, 1963.] [Privat A and Leblond CP. The subependymal layer and neighboring region in the brain of the young rat. J Comp Neurol 146: 277–302, 1972] [Smart I. The subependymal layer of the mouse brain and its cell production as shown by radioautography after thymidine-H3 injection. J Comp Neurol 116: 325–347, 1961.] , monkeys [Gould E, Reeves AJ, Fallah M, Tanapat P, Gross CG, and Fuchs E. Hippocampal neurogenesis in adult Old World primates. Proc Natl Acad Sci USA 96: 5263–5267, 1999.] [Gould E, Reeves AJ, Graziano MS, and Gross CG. Neurogenesis in the neocortex of adult primates. Science 286: 548–552, 1999.] [Gould E, Vail N, Wagers M, and Gross CG. Adult-generated hippocampal and neocortical neurons in macaques have a transient existence. Proc Natl Acad Sci USA 98: 10910–10917, 2001.] [Kaplan MS. Formation and turnover of neurons in young and senescent animals: an electronmicroscopic and morphometric analysis. Ann NY Acad Sci 457: 173–192, 1985.] [Kornack DR and Rakic P. The generation, migration, and differentiation of olfactory neurons in the adult primate brain. Proc Natl Acad Sci USA 98: 4752–4757, 2001.] [Pencea V, Bingaman KD, Freedman LJ, and Luskin MB. Neurogenesis in the subventricular zone and rostral migratory stream of the neonatal and adult primate forebrain. Exp Neurol 172: 1–16, 2001.] and humans [Bernier PJ, Vinet J, Cossette M, and Parent A. Characterization of the subventricular zone of the adult human brain: evidence for the involvement of Bcl-2. Neurosci Res 37: 67–78, 2000.] [Eriksson PS, Perfilieva E, Bjork-Eriksson T, Alborn AM, Nordborg C, Peterson DA, and Gage FH. Neurogenesis in the adult human hippocampus. Nat Med 4: 1313–1317, 1998.] . Neurons generated in SVZ travel to the olfactory bulb via the rostral migratory stream, which has until recently remained elusive in humans. [H. Troy Ghashghaei, Cary Lai, E. S. Anton. Neuronal migration in the adult brain: are we there yet? Nature Reviews: Neuroscience, Volume 8: 141-151, 2007] [Human Neuroblasts Migrate to the Olfactory Bulb via lateral Ventricular Extension. Science V. 315, p. 1243 (2007)]

Four cell types have been described in the SVZ:

* ciliated ependymal cells (type E) facing the lumen of the ventricle, whose function is to circulate the cerebrospinal fluid;
* proliferating type A neuroblasts, expressing PSA-NCAM, Tuj1, and Hu, and migrating in "chains" toward the olfactory bulb (OB);
* slowly proliferating type B cells expressing nestin and GFAP, and unsheathing migrating type A neuroblasts
* actively proliferating type C cells or "transit amplifying progenitors" expressing nestin, and forming clusters interspaced among chains throughout the SVZ

Literature

* Abrous DN, Koehl M, Le Moal M. (2005) "Adult neurogenesis: from precursors to network and physiology." Physiol Rev. 85(2):523-69. PMID 15788705 [http://physrev.physiology.org/cgi/content/full/85/2/523 free fulltext]

* Alvarez-Buylla A, Garcia-Verdugo JM. (2002) "Neurogenesis in adult subventricular zone." J Neurosci. 22(3):629-34. PMID 11826091 [http://www.jneurosci.org/cgi/content/full/22/3/629 free fulltext]

External links

* [http://www.gsf.de/idg/groups/adult_neurogenesis/captions_3.html Model of neurogenesis in the subventricular zone (SVZ) /olfactory bulb system]

References