Adult neurogenesis in the telencephalon of a lizard: a [3H]thymidine autoradiographic and bromodeoxyuridine immunocytochemical study
TL;DR: It is concluded that neurogenesis occur in most regions of the adult lizard telencephalon, and the most intense neuronal production occurs in the MC, which is restricted to areas that have been implicated in olfactory plasticity, learning, and memory.
About: This article is published in Developmental Brain Research.The article was published on 1996-05-31. It has received 92 citations till now. The article focuses on the topics: Neurogenesis & Bromodeoxyuridine.
Citations
More filters
TL;DR: New anatomical studies of the central pathways of the olfactory and vomeronasal systems indicated that these two systems converge on neurons in the telencephalon, providing an anatomical substrate for functional interactions.
587 citations
Additional excerpts
..., 1996) , reptiles (Garcia-Verdugo et al., 1989; Perez-Canellas and Garcia-Verdugo, 1996; Perez-Canellas et al., 1997) and mammals(Altman, 1969; Altman and Das, 1966; Bayer, 1983; Hinds, 1968a,b; Kaplan and Hinds, 1977; Kaplan et al....
[...]
TL;DR: Using BrdU tracing and immunodetection of cell-type-specific markers, it is demonstrated that the adult zebrafish telencephalon contains self-renewing progenitors, which show features of adult mammalian neural stem cells but distribute along the entire dorso-ventral extent of theTelencephalic ventricular zone.
392 citations
Cites background from "Adult neurogenesis in the telenceph..."
..., 2002) by a short migration to the parenchyma close to the VZ of the dorsal telencephalon (Perez-Canellas and Garcia-Verdugo, 1996)....
[...]
...Interestingly, also in reptiles newborn neurons populate all major subdivisions of the cortex (Font et al., 2001; Garcia-Verdugo et al., 2002) by a short migration to the parenchyma close to the VZ of the dorsal telencephalon (Perez-Canellas and Garcia-Verdugo, 1996)....
[...]
TL;DR: BdU‐labeled cells remained present in the brain over at least 292 days post‐BrdU administration, indicating a long‐term survival of a significant portion of the newly generated cells, and suggested a neuronal differentiation in a large portions of the young cells.
Abstract: In contrast to mammals, fish exhibit an enormous potential to produce new cells in the adult brain. By labeling mitotically dividing cells with 5-bromo-2'-deoxyuridine (BrdU), we have characterized the development of these cells in the zebrafish (Danio rerio). Proliferation zones were located in specific regions of the olfactory bulb, dorsal telencephalon (including a region presumably homologous to the mammalian hippocampus), preoptic area, dorsal zone of the periventricular hypothalamus, optic tectum, torus longitudinalis, vagal lobe, parenchyma near the rhombencephalic ventricle, and in a region of the medulla oblongata lateral to the vagal motor nucleus, as well as in all three subdivisions of the cerebellum, the valvula cerebelli, the corpus cerebelli, and the lobus caudalis cerebelli. In the valvula cerebelli and the corpus cerebelli, the young cells migrated from their site of origin in the molecular layers to the corresponding granule cell layers. By contrast, in the lobus caudalis cerebelli and optic tectum, no indication of a migration of the newly generated cells over wider distances could be obtained. BrdU-labeled cells remained present in the brain over at least 292 days post-BrdU administration, indicating a long-term survival of a significant portion of the newly generated cells. The combination of BrdU immunohistochemistry with immunolabeling against the neural marker protein Hu, or with retrograde tracing, suggested a neuronal differentiation in a large portion of the young cells.
355 citations
TL;DR: The argument that specialization of the mitotic compartments may constitute a major drive behind the evolution of the mammalian cortex is presented, drawing attention to the limitations of some of the current model systems for understanding human developmental abnormalities of the cortex.
Abstract: This review aims to provide examples of how both comparative and genetic analyses contribute to our understanding of the rules for cortical development and evolution. Genetic studies have helped us to realize the evolutionary rules of telencephalic organization in vertebrates. The control of the establishment of conserved telencephalic subdivisions and the formation of boundaries between these subdivisions has been examined and the very specific alterations at the striatocortical junction have been revealed. Comparative studies and genetic analyses both demonstrate the differential origin and migratory pattern of the two basic neuron types of the cerebral cortex. GABAergic interneurons are mostly generated in the subpallium and a common mechanism governs their migration to the dorsal cortex in both mammals and sauropsids. The pyramidal neurons are generated within the cortical germinal zone and migrate radially, the earliest generated cell layers comprising preplate cells. Reelin-positive Cajal-Retzius cells are a general feature of all vertebrates studied so far; however, there is a considerable amplification of the Reelin signalling with cortical complexity, which might have contributed to the establishment of the basic mammalian pattern of cortical development. Based on numerous recent observations we shall present the argument that specialization of the mitotic compartments may constitute a major drive behind the evolution of the mammalian cortex. Comparative developmental studies have revealed distinct features in the early compartments of the developing macaque brain, drawing our attention to the limitations of some of the current model systems for understanding human developmental abnormalities of the cortex. Comparative and genetic aspects of cortical development both reveal the workings of evolution.
255 citations
TL;DR: It is argued that comprehensive analyses of adult neurogenesis in various vertebrate and invertebrate species will lead to a more complete understanding of the fundamental biology and evolution of adult Neurogenesis and provide a better framework for testing hypotheses regarding the functional significance of this trait.
205 citations
References
More filters
TL;DR: PAP was heterogeneous on electrophoresis, homogeneous on sedimentation, diffusion and electron microscopy and consisted of pentagons with diameters of 205 Å, with the unexpected ratio of PO to anti-PO presumed to be due to stabilization by the pentagonal shape.
Abstract: Antigen was identified histochemically without the use of labeled antibodies by the sequential application of (a) specific rabbit antiserum, (b) sheep antiserum to rabbit immunoglobulin G, (c) specifically purified, soluble horseradish peroxidase-anti-horseradish peroxidase complex (PAP), (d) 3,3'-diaminobenzidine and hydrogen peroxide and (e) osmium tetroxide. A simple method for preparation of high yields of PAP consisted of precipitation of antibody from specific rabbit antiserum with horseradish peroxidase (PO) at equivalence, solubilization of the washed precipitate with excess PO at pH 2.3, 1°C, followed by immediate neutralization and separation of PAP from PO by half-saturation with ammonium sulfate. The ratio of PO to anti-PO in PAP was 3:2 irrespective of the source of antiserum. PAP was heterogeneous on electrophoresis, homogeneous on sedimentation, diffusion and electron microscopy and consisted of pentagons with diameters of 205 A. s20,w, 11.98 x 10–13; d20,w, 2.48 x 10–7; molecular weight by...
5,135 citations
TL;DR: Grafted and endogenous SVZ cells in the lateral ventricle of adult mice migrate long distances and differentiate into neurons in the olfactory bulb.
Abstract: During the development of the mammalian brain, neuronal precursors migrate to their final destination from their site of birth in the ventricular and subventricular zones (VZ and SVZ, respectively). SVZ cells in the walls of the lateral ventricle continue to proliferate in the brain of adult mice and can generate neurons in vitro, but their fate in vivo is unknown. Here SVZ cells from adult mice that carry a neuronal-specific transgene were grafted into the brain of adult recipients. In addition, the fate of endogenous SVZ cells was examined by microinjection of tritiated thymidine or a vital dye that labeled a discrete population of SVZ cells. Grafted and endogenous SVZ cells in the lateral ventricle of adult mice migrate long distances and differentiate into neurons in the olfactory bulb.
2,325 citations
TL;DR: The SVZa appears to constitute a specialized source of neuronal progenitor cells that differentiated into granule cells and periglomerular cells of the olfactory bulb-the two major types of interneurons.
1,837 citations
TL;DR: Three-month-old rats were injected intraperitoneally with [3H]thymidine and labeled cells in the granular layers of dentate gyrus and olfactory bulb were confirmed as neurons by electron microscopy of reembedded 1-micrometer sections.
Abstract: Three-month-old rats were injected intraperitoneally with [3H]thymidine (4.3 microcuries per gram of body weight) and allowed to survive for 30 days. Radioautography of 1-micrometer sections revealed labeled cells in the granular layers of dentate gyrus and olfactory bulb; these were confirmed as neurons by electron microscopy of reembedded 1-micrometer sections.
1,495 citations
TL;DR: It is concluded that neuronal precursors exist in the HVc ventricular zone that incorporate tritiated thymidine during the S phase preceding their mitosis; after division these cells migrate into, and to some extent beyond, HVm, which seems to be a normally occurring phenomenon in intact adult female canaries.
Abstract: The vocal control nucleus designated HVc (hyperstriatum ventrale, pars caudalis) of adult female canaries expands in response to systemic testosterone administration, which also induces the females to sing in a male-like manner. We became interested in the possibility of neurogenesis as a potential basis for this phenomenon. Intact adult female canaries were injected with [3H]thymidine over a 2-day period. Some birds were given testosterone implants at various times before thymidine. The birds were sacrificed 5 wk after hormone implantation, and their brains were processed for autoradiography. In parallel control experiments, some birds were given implants of cholesterol instead of testosterone. All birds showed considerable numbers of labeled neurons, glia, endothelia, and ventricular zone cells in and around HVc. Ultrastructural analysis confirmed the identity of these labeled neurons. Cholesterol- and testosterone-treated birds had similar neuronal labeling indices, which ranged from 1.8% to 4.0% in HVc. Thus, neurogenesis occurred in these adults independently of exogenous hormone treatment. Conversely, both glial and endothelial proliferation rates were markedly stimulated by exogenous testosterone treatment. We determined the origin of the thymidine-incorporating neurons by sacrificing two thymidine-treated females soon after their thymidine injections, precluding any significant migration of newly labeled cells. Analysis of these brains revealed no cells of neuronal morphology present in HVc but a very heavily labeled ventricular zone overlying HVc. We conclude that neuronal precursors exist in the HVc ventricular zone that incorporate tritiated thymidine during the S phase preceding their mitosis; after division these cells migrate into, and to some extent beyond, HVc. This ventricular zone neurogenesis seems to be a normally occurring phenomenon in intact adult female canaries.
992 citations