Persistence of Functional Sensory Maps in the Absence of Cortical Layers in the Somsatosensory Cortex of Reeler Mice.
In rodents, layer IV of the primary somatosensory cortex contains the barrel field, where individual, large facial whiskers are represented as a dense cluster of cells. In the reeler mouse, a model of disturbed cortical development characterized by a loss of cortical lamination, the barrel field exists in a distorted manner. Little is known about the consequences of such a highly disturbed lamination on cortical function in this model. We used in vivo intrinsic signal optical imaging together with piezo-controlled whisker stimulation to explore sensory map organization and stimulus representation in the barrel field. We found that the loss of cortical layers in reeler mice had surprisingly little incidence on these properties. The overall topological order of whisker representations is highly preserved and the functional activation of individual whisker representations is similar in size and strength to wild-type controls. Because intrinsic imaging measures hemodynamic signals, we furthermore investigated the cortical blood vessel pattern of both genotypes, where we also did not detect major differences. In summary, the loss of the reelin protein results in a widespread disturbance of cortical development which compromises neither the establishment nor the function of an ordered, somatotopic map of the facial whiskers.
Institut für Neuroanatomie, Universitätsmedizin Göttingen, Georg-August-Universität, Göttingen D-37075, Germany julien.guy@med.uni-goettingen.de.
Julien
J
Guy
Institut für Neuroanatomie, Universitätsmedizin Göttingen, Georg-August-Universität, Göttingen D-37075, Germany.
Robin J
RJ
Wagener
Institut für Neuroanatomie, Universitätsmedizin Göttingen, Georg-August-Universität, Göttingen D-37075, Germany.
Martin
M
Möck
Institut für Neuroanatomie, Universitätsmedizin Göttingen, Georg-August-Universität, Göttingen D-37075, Germany.
Jochen F
JF
Staiger
D000344:Afferent Pathways / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001931:Brain Mapping; D004195:Disease Models, Animal; D053503:Epithelial Sodium Channels / Q000235:genetics / Q000378:metabolism; D021621:Imaging, Three-Dimensional; D054220:Malformations of Cortical Development / Q000235:genetics / Q000473:pathology*; D051379:Mice; D008818:Mice, Neurologic Mutants; D008822:Mice, Transgenic; D062308:Optogenetics; D010812:Physical Stimulation; D037121:Plant Lectins / Q000235:genetics / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics / Q000378:metabolism; D000091042:Reelin Protein; D013003:Somatosensory Cortex / Q000473:pathology* / Q000503:physiopathology*; D013997:Time Factors; D014738:Vibrissae / Q000294:innervation
D053503:Epithelial Sodium Channels; C110853:Gt(ROSA)26Sor non-coding RNA, mouse; D037121:Plant Lectins; D022661:RNA, Untranslated; D000091042:Reelin Protein; C507047:Scnn1a protein, mouse; C034981:tomato lectin; C000717128:Reln protein, mouse
barrel field; cortical blood vessels; intrinsic signal optical imaging; reeler; somatotopy