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. 2009 Jun 9:3:7.
doi: 10.3389/neuro.05.007.2009. eCollection 2009.

Neurons in the white matter of the adult human neocortex

M Luisa Suárez-Solá  1 , Francisco J González-Delgado, Mercedes Pueyo-Morlans, O Carolina Medina-Bolívar, N Carolina Hernández-Acosta, Miriam González-Gómez, Gundela Meyer
Affiliations

Neurons in the white matter of the adult human neocortex

M Luisa Suárez-Solá et al. Front Neuroanat. .

Abstract

The white matter (WM) of the adult human neocortex contains the so-called "interstitial neurons". They are most numerous in the superficial WM underlying the cortical gyri, and decrease in density toward the deep WM. They are morphologically heterogeneous. A subgroup of interstitial neurons display pyramidal-cell like morphologies, characterized by a polarized dendritic tree with a dominant apical dendrite, and covered with a variable number of dendritic spines. In addition, a large contingent of interstitial neurons can be classified as interneurons based on their neurochemical profile as well as on morphological criteria. WM- interneurons have multipolar or bipolar shapes and express GABA and a variety of other neuronal markers, such as calbindin and calretinin, the extracellular matrix protein reelin, or neuropeptide Y, somatostatin, and nitric oxide synthase. The heterogeneity of interstitial neurons may be relevant for the pathogenesis of Alzheimer disease and schizophrenia. Interstitial neurons are most prominent in human brain, and only rudimentary in the brain of non-primate mammals. These evolutionary differences have precluded adequate experimental work on this cell population, which is usually considered as a relict of the subplate, a transient compartment proper of development and without a known function in the adult brain. The primate-specific prominence of the subplate in late fetal stages points to an important role in the establishment of interstitial neurons. Neurons in the adult WM may be actively involved in coordinating inter-areal connectivity and regulation of blood flow. Further studies in primates will be needed to elucidate the developmental history, adult components and activities of this large neuronal system.

Keywords: Tbr1; calretinin; neuropeptide Y; nitric oxide synthase; schizophrenia; subplate.

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Figures

Figure 1
Figure 1
Tbr1 marks glutamatergic neurons in the human subplate (SP). (A) At 10 gestational weeks (GW), highest Tbr1 staining is in the early cortical plate (CP). (B) At 16 GW, Tbr1+ cells are concentrated along the CP/SP border and distributed all over the SP. (C) At 25 GW, the SP, here in the temporal lobe, has increased in width and is filled with Tbr1+ neurons extending from the intermediate zone (IZ) to the deep CP border. The growth of the SP despite the expansion of the cortical wall indicates the continuous addition of new Tbr1+ neurons. HC, hippocampus; SVZ, subventricular zone; VZ, ventricular zone. Scale bar in (A) 100 μm, in (B) 200 μm, in (C) 1 mm.
Figure 2
Figure 2
The variety of IN in the adult human WM. (A) CR+ IN are the most abundant cell class in the superficial WM. (B) NPY+ IN (arrows) in the superficial WM. They may be the origin of the fiber terminals in layer VI, indicated by arrowheads. (C) A bipolar CB+ IN in the deep WM. The arrowhead points to an axonal ramification site. (D) A multipolar CB+ IN in the superficial WM. (E) A Reelin+ IN in the superficial WM. Scale bar in (A) 200 μm, in (B) 150 μm, in (C) 30 μm, in (D) 20 μm, in (E) 15 μm.
Figure 3
Figure 3
CR+ neurons in the deep WM of the temporal lobe. (A,B) Clusters of small neurons are concentrated near blood vessels. The arrows point to fibers running along the vascular wall. (C) Cluster in the deep WM. The dense local axonal plexus is mostly confined to the cluster, with few fibers extending into the neighboring WM. The arrowhead points to an axon contacting a soma. Scale bar in (A) 50 μm, in (B) 100 μm, in (C) 50 μm.
Figure 4
Figure 4
(A) Type 1 NADPH-d+ neurons in the superficial WM. (B) Magnified view of a type 1 neuron near a microvessel that is contacted by NADPH-d+ axonal fibers (arrowheads). Scale bar in (A) 150 μm; in (B) 20 μm.
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References

    1. Abounader R., Hamel E. (1997). Associations between neuropeptide Y nerve terminals and intraparenchymal microvessels in rat and human cerebral cortex. J. Comp. Neurol. 388, 444–453 10.1002/(SICI)1096-9861(19971124)388:3<444::AID-CNE7>3.0.CO;2-0 - DOI - PubMed
    1. Akbarian S., Bunney W. E., Potkin S. G., Wigal S. B., Hagman J. O., Sandman C. A., Jones E. G. (1993). Altered distribution of nicotinamide-adenine dinucleotide phosphate-diaphorase cells in frontal lobe of schizophrenics implies disturbances of cortical development. Arch. Gen. Psychiatry 50, 169–177 - PubMed
    1. Akbarian S., Kim J. J., Potkin S. G., Hetrick W. P., Bunney W. E., Jones E. G. (1996). Maldistribution of interstitial neurons in prefrontal white matter of the brains of schizophrenic patients. Arch. Gen. Psychiatry 53, 425–436 - PubMed
    1. Allendoerfer K. L., Shatz C. J. (1994). The subplate, a transient neocortical structure, its role in the development of connections between thalamus and cortex. Annu. Rev. Neurosci. 17, 185–218 10.1146/annurev.ne.17.030194.001153 - DOI - PubMed
    1. Ascoli G. A., Alonso-Nanclares L., Anderson S. A., Barrionuevo G., Benavides-Piccione R., Burkhalter A., Buzsáki G., Cauli B., Defelipe J., Fairén A., Feldmeyer D., Fishell G., Fregnac Y., Freund T. F., Gardner D., Gardner E. P., Goldberg J. H., Helmstaedter M., Hestrin S., Karube F., Kisvárday Z. F., Lambolez B., Lewis D. A., Marin O., Markram H., Muñoz A., Packer A., Petersen C. C., Rockland K. S., Rossier J., Rudy B., Somogyi P., Staiger J. F., Tamas G., Thomson A. M., Toledo-Rodriguez M., Wang Y., West D. C., Yuste R. (2008). Petilla terminology, nomenclature of features of GABAergic interneurons of the cerebral cortex. Nat. Rev. Neurosci. 9, 557–568 10.1038/nrn2402 - DOI - PMC - PubMed

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