Changes in cell migration and survival in the olfactory bulb of the pcd/pcd mouse.
Postnatally, the Purkinje cell degeneration mutant mice lose the main projecting neurons of the main olfactory bulb (OB): mitral cells (MC). In adult animals, progenitor cells from the rostral migratory stream (RMS) differentiate into bulbar interneurons that modulate MC activity. In the present work, we studied changes in proliferation, tangential migration, radial migration patterns, and the survival of these newly generated neurons in this neurodegeneration animal model. The animals were injected with bromodeoxyuridine 2 weeks or 2 months before killing in order to label neuroblast incorporation into the OB and to analyze the survival of these cells after differentiation, respectively. Both the organization and cellular composition of the RMS and the differentiation of the newly generated neurons in the OB were studied using specific markers of glial cells, neuroblasts, and mature neurons. No changes were observed in the cell proliferation rate nor in their tangential migration through the RMS, indicating that migrating neuroblasts are only weakly responsive to the alteration in their target region, the OB. However, the absence of MC does elicit differences in the final destination of the newly generated interneurons. Moreover, the loss of MC also produces changes in the survival of the newly generated interneurons, in accordance with the dramatic decrease in the number of synaptic targets available.
Valero
J
J
Lab Plasticidad Neuronal y Neurorreparación, Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, E-37007 Salamanca, Spain.
Weruaga
E
E
Murias
A R
AR
Recio
J S
JS
Curto
G G
GG
Gómez
C
C
Alonso
J R
JR
D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001973:Bromodeoxyuridine; D015816:Cell Adhesion Molecules, Neuronal / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology*; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D004195:Disease Models, Animal; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D020287:In Situ Nick-End Labeling; D007395:Interneurons / Q000166:cytology / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009410:Nerve Degeneration / Q000378:metabolism / Q000503:physiopathology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009457:Neuroglia / Q000166:cytology / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D009830:Olfactory Bulb / Q000166:cytology / Q000502:physiology*; D000091042:Reelin Protein; D012697:Serine Endopeptidases / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*
D015415:Biomarkers; D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D009419:Nerve Tissue Proteins; D000091042:Reelin Protein; D012697:Serine Endopeptidases; D001973:Bromodeoxyuridine