Article

Dendritic development and plasticity of adult-born neurons in the mouse olfactory bulb.

Department of Neurobiology, Institue for Life Sciences and the Interdisciplinary Center for Neural Computation, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel.
Nature Neuroscience (Impact Factor: 14.98). 05/2007; 10(4):444-52. DOI: 10.1038/nn1875
Source: PubMed

ABSTRACT The mammalian brain maintains few developmental niches where neurogenesis persists into adulthood. One niche is located in the olfactory system where the olfactory bulb continuously receives functional interneurons. In vivo two-photon microscopy of lentivirus-labeled newborn neurons was used to directly image their development and maintenance in the olfactory bulb. Time-lapse imaging of newborn neurons over several days showed that dendritic formation is highly dynamic with distinct differences between spiny neurons and non-spiny neurons. Once incorporated into the network, adult-born neurons maintain significant levels of structural dynamics. This structural plasticity is local, cumulative and sustained in neurons several months after their integration. Thus, I provide a new experimental system for directly studying the pool of regenerating neurons in the intact mammalian brain and suggest that regenerating neurons form a cellular substrate for continuous wiring plasticity in the olfactory bulb.

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    • "This hypothesis implies that comparisons of adult OB and DG functions with neuronal functions of young neurons during neurodevelopment may lead to useful insights. Adult born neurons in the OB undergo structural plasticity throughout their maturation and integration into OB circuits (Mizrahi, 2007). Reducing OB circuit activity lowers dendritic complexity and dendritic spine number (Dahlen et al., 2011). "
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    Frontiers in Neuroanatomy 07/2013; 7(21). DOI:10.3389/fnana.2013.00021
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    • "To retrieve information over this higher anatomical level, the structures of interest must be either entirely imaged or reconstructed from serially sectioned material. Recent advances in light microscopy and in molecular and genetic manipulations have greatly extended the possibility of imaging large volumes of both fixed and live neural tissue at cellular resolution, enabling the visualization of complex 3D objects such as neuronal or vascular networks (Mizrahi, 2007; Lu et al., 2009; Tsai et al., 2009; Wilt et al., 2009; Khairy and Keller, 2011). These imaging techniques represent a pivotal innovation for multiple neuroanatomical fields ranging from the definition of comprehensive maps anti-goat biotinylated secondary antibody for 1 h (1:250; Vector Laboratories, Burlingame, CA, USA), rinsed, and incubated in avidin–biotin complex (1:400; Vector Laboratories). "
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    Frontiers in Neuroscience 05/2011; 5:70. DOI:10.3389/fnins.2011.00070
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    • "Over time, many types of neurons exhibit a reduction in structural plasticity, with neurons progressively reducing branch dynamics and stabilizing their dendritic arbors. Even in the case of adult-born neurons that integrate into existing neural circuits, dendrites enter a maintenance phase after a short period of dynamic growth and dendrite arbor rearrangement (Grutzendler et al. 2002; Trachtenberg et al. 2002; Mizrahi 2007). However, dendritic arbors of mature neurons often undergo a large-scale remodeling under pathological conditions such as epilepsy and after ischemia. "
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