title: Development of the innervation of the human inner ear.
abstract: Studies on the formation of neuronal structures of the human cochlea are rare, presumptively, due to the difficult accessibility of specimens, so that most investigations are performed on mouse models. By means of immunohistochemical and transmission electron microscopic techniques, we investigated an uninterrupted series of unique specimens from gestational week 8 to week 12. We were able to demonstrate the presence of nerve fibers in the prosensory domain at gestational week 8, followed by afferent synaptogenesis at week 11. We identified PAX2 as an early marker for hair cell differentiation. Glutamine synthetase-positive peripheral glial cells occurred at the beginning of week 8. Transcription factor MAF B was used to demonstrate maturation of the spiral ganglion neurons. The early expression of tyrosine hydroxylase could be assessed. This study provides insights in the early assembly of the neural circuit and organization in humans.
authors.affiliation: Department of Anatomy, Histology, and Embryology, Division of Clinical and Functional Anatomy, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria.
authors.forename: Elisabeth J
authors.initials: EJ
authors.lastname: Pechriggl
authors.affiliation: Department of Anatomy, Histology, and Embryology, Division of Clinical and Functional Anatomy, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria.
authors.forename: Mario
authors.initials: M
authors.lastname: Bitsche
authors.affiliation: Department of Otolaryngology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria.|University Clinics Innsbruck, Tiroler Landeskrankenanstalten, Innsbruck, Austria.
authors.forename: Rudolf
authors.initials: R
authors.lastname: Glueckert
authors.affiliation: Departments of Otolaryngology, Uppsala University Hospital, 751 85, Uppsala, Sweden.
authors.forename: Helge
authors.initials: H
authors.lastname: Rask-Andersen
authors.affiliation: Department of Anatomy, Histology, and Embryology, Division of Clinical and Functional Anatomy, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria.
authors.forename: Michael J F
authors.initials: MJ
authors.lastname: Blumer
authors.affiliation: Department of Otolaryngology, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria.
authors.forename: Annelies
authors.initials: A
authors.lastname: Schrott-Fischer
authors.affiliation: Department of Anatomy, Histology, and Embryology, Division of Clinical and Functional Anatomy, Medical University of Innsbruck, Müllerstrasse 59, 6020, Innsbruck, Austria.
authors.forename: Helga
authors.initials: H
authors.lastname: Fritsch
mesh_terms: D000328:Adult; D007758:Ear, Inner / Q000254:growth & development* / Q000294:innervation* / Q000378:metabolism; D005333:Fetus; D006801:Humans; D007150:Immunohistochemistry; D051258:MafB Transcription Factor / Q000378:metabolism; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D051762:PAX2 Transcription Factor / Q000378:metabolism; D064531:Peripherins / Q000378:metabolism; D013136:Spiral Ganglion / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D013569:Synapses / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
chemical_list: C490407:MAFB protein, human; D051258:MafB Transcription Factor; D051762:PAX2 Transcription Factor; C497318:PAX2 protein, human; C578994:PRPH protein, human; D064531:Peripherins; C498585:TUBB3 protein, human; D014404:Tubulin; D014446:Tyrosine 3-Monooxygenase
keywords: BDNF; MAF B; PAX2; early development; glutamine synthetase; inner ear; innervation