Document Detail


Mild, non-lesioning transient hypoxia in the newborn rat induces delayed brain neurogenesis associated with improved memory scores.
MedLine Citation:
PMID:  16650606     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Although neonatal hypoxia can lead to brain damage, mild hypoxic episodes may be beneficial, as illustrated by tolerance induction by preconditioning, a process that might involve neurogenesis. To examine if brief hypoxia in newborn rats could stimulate the generation of neurons, pups were exposed for 5 min to 100% N2. Cell density and apoptosis were monitored in various brain regions and cell proliferation was studied by the incorporation of bromodeoxyuridine. Hypoxia did not result in detectable cell death but promoted cell proliferation in the ensuing three weeks in the subventricular zone and hippocampal dentate gyrus, with increased cell density in hippocampus CA1 pyramidal cells and granular layer of the dentate gyrus. Newly generated cells expressed neuronal markers (NeuroD or neuronal nuclear antigen) and were able to migrate from germinative zones to specific sites, in particular from the subventricular zone to the CA1 layer along the posterior periventricle. Neurogenesis was associated with an early activation of the extracellular regulated kinase 1/2 pathway, and pre-hypoxic administration of U0126, an inhibitor of mitogen-activated protein kinase kinase, impaired hypoxia effect on cell proliferation. Neurobehavioral capacities of hypoxic rats paralleled those of controls, but early exposure to hypoxia was associated with significantly improved memory retrieval scores at 40 days. In conclusion, brief neonatal hypoxia may trigger delayed generation of potentially functional neurons without concomitant cell death. This may constitute an interesting model for studying cell key events involved in the induction of neurogenesis.
Authors:
G Pourié; S Blaise; M Trabalon; E Nédélec; J-L Guéant; J-L Daval
Related Documents :
8787776 - Phagocytozing ameboid microglial cells studied in a mouse corpus callosum slice prepara...
19915696 - Ape1/ref-1 stimulates gdnf/gfralpha1-mediated downstream signaling and neuroblastoma pr...
1362196 - Retinoic acid increases cd15 expression in immortalized rat astrocytes.
6406066 - 6-ohda-induced ectopia of external granule cells in the subarachnoid space covering the...
23985926 - Non-uniformity of cell density and networks in the monkey brain.
22190546 - Study on the autophagy of prostate cancer pc-3 cells induced by oridonin.
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't     Date:  2006-05-02
Journal Detail:
Title:  Neuroscience     Volume:  140     ISSN:  0306-4522     ISO Abbreviation:  Neuroscience     Publication Date:  2006 Jul 
Date Detail:
Created Date:  2006-07-03     Completed Date:  2006-10-26     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  7605074     Medline TA:  Neuroscience     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1369-79     Citation Subset:  IM    
Affiliation:
INSERM U. 724, Faculté de Médecine, UHP, 9 avenue de la Forêt de Haye, B.P. 184, 54505 Vandoeuvre-les-Nancy Cedex, France.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Animals, Newborn
Brain / cytology*,  growth & development*
Hypoxia, Brain* / pathology
Memory / physiology*
Neurons / cytology*,  physiology
Rats
Rats, Wistar

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Intron retention as an alternative splice variant of the rat urocortin 1 gene.
Next Document:  Insulin-like growth factor I interfaces with brain-derived neurotrophic factor-mediated synaptic pla...