Subplate
The transient fetal subplate zone, together with the marginal zone and the cortical plate, represents the developmental anlage of the mammalian cerebral cortex. It serves as a waiting compartment for growing cortical afferents; its cells are involved in the establishment of pioneering cortical efferent projections and transient fetal circuitry, and apparently have a number of other developmental roles. The subplate zone is a phylogenetically recent structure and it is most developed in the human brain.
Subplate neurons are among the first generated neurons in the mammalian cerebral cortex [1]. These neurons disappear during postnatal development and are important in establishing the correct wiring [2][3] and functional maturation [4] of the cerebral cortex. Subplate neurons appear to be selectively sensitive to injury (such as hypoxia) which in humans are associated with motor and cognitive defects [5].
Subplate neurons are the first cortical neurons to receive synaptic inputs from thalamic axons, establishing a temporary link between thalamic axons and their final target in layer 4. [6][7][8]. Later, thalamic axons invade layer 4 where they innervate layer 4 neurons. In the visual system thalamic axons to layer 4 form ocular dominance columns and this segregation of thalamic axons is impaired if subplate neurons are missing [9][10].
References
- ^ Ghosh A, Shatz CJ (March 1992). "Involvement of subplate neurons in the formation of ocular dominance columns". Science 255 (5050): 1441–3. doi:10.1126/science.1542795. PMID 1542795. http://www.sciencemag.org/cgi/pmidlookup?view=long&pmid=1542795.
- ^ Friauf E, McConnell SK, Shatz CJ (August 1990). "Functional synaptic circuits in the subplate during fetal and early postnatal development of cat visual cortex". J. Neurosci. 10 (8): 2601–13. PMID 2388080. http://www.jneurosci.org/cgi/pmidlookup?view=long&pmid=2388080.
- ^ Rakic P (April 1977). "Prenatal development of the visual system in rhesus monkey". Philos. Trans. R. Soc. Lond., B, Biol. Sci. 278 (961): 245–60. doi:10.1098/rstb.1977.0040. PMID 19781. http://rstb.royalsocietypublishing.org/cgi/pmidlookup?view=long&pmid=19781.
- ^ Kostovic I, Rakic P (April 1980). "Cytology and time of origin of interstitial neurons in the white matter in infant and adult human and monkey telencephalon". J. Neurocytol. 9 (2): 219–42. doi:10.1007/BF01205159. PMID 7441294.
- ^ McConnell SK, Ghosh A, Shatz CJ (September 1989). "Subplate neurons pioneer the first axon pathway from the cerebral cortex". Science 245 (4921): 978–82. doi:10.1126/science.2475909. PMID 2475909. http://www.sciencemag.org/cgi/pmidlookup?view=long&pmid=2475909.
- ^ Kanold PO, Kara P, Reid RC, Shatz CJ (July 2003). "Role of subplate neurons in functional maturation of visual cortical columns". Science 301 (5632): 521–5. doi:10.1126/science.1084152. PMID 12881571. http://www.sciencemag.org/cgi/pmidlookup?view=long&pmid=12881571.
- ^ McQuillen PS, Ferriero DM (July 2005). "Perinatal subplate neuron injury: implications for cortical development and plasticity". Brain Pathol. 15 (3): 250–60. doi:10.1111/j.1750-3639.2005.tb00528.x. PMID 16196392.
See also