title: In vitro reconstitution of signal transmission from a hair cell to the growth cone of a chick vestibular ganglion cell.
abstract: Signal transmission from a chick hair cell to the growth cone of a vestibular ganglion cell was examined by placing an acutely dissociated hair cell on the growth cone of a cultured vestibular ganglion cell. Electrical stimuli were applied to the hair cell while monitoring the intracellular Ca(2+) concentration ([Ca(2+)](i)) at the growth cone or recording whole-cell currents from the vestibular ganglion cell. Electrical stimulation of the hair cell induced [Ca(2+)](i) increases at the growth cone and inward currents in the vestibular ganglion cell. The [Ca(2+)](i) increase was blocked by 6-cyano-7-nitroquinoxaline (CNQX) (10 microM) but not by 2-amino-5-phosphonovaleric acid (APV; 50 microM). Glutamate (100 nM-300 microM) applied to the vestibular ganglion cell by the Y-tube method induced inward currents which were also antagonized by CNQX, but not by APV. These results indicate that the electrical stimulation of a hair cell induced glutamate or glutamate like agent release from the hair cell, which activated non-N-methyl-D-aspartate receptors at the growth cone of the vestibular ganglion cell, followed by action potentials and [Ca(2+)](i) elevation in the vestibular ganglion cell. This is the first demonstration of in vitro reconstitution of functional signal transmission from a hair cell to a vestibular ganglion cell.
authors.affiliation: Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, 466-8550, Nagoya, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hoshino
authors.forename: H
authors.initials: H
authors.lastname: Tatsumi
authors.forename: T
authors.initials: T
authors.lastname: Nakashima
authors.forename: M
authors.initials: M
authors.lastname: Sokabe
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D016257:Fura-2 / Q000031:analogs & derivatives* / Q000378:metabolism; D017950:Ganglia, Sensory / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D018698:Glutamic Acid / Q000494:pharmacology; D020439:Growth Cones / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D018069:Hair Cells, Vestibular / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D009431:Neural Conduction / Q000187:drug effects; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D013997:Time Factors; D014633:Valine / Q000031:analogs & derivatives* / Q000494:pharmacology; D014722:Vestibule, Labyrinth / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*
chemical_list: D018691:Excitatory Amino Acid Antagonists; D018091:Receptors, AMPA; C104723:glutamate receptor ionotropic, AMPA 3; C049925:fura-2-am; D018698:Glutamic Acid; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; C056639:2-amino-5-phosphopentanoic acid; D014633:Valine; C104722:glutamate receptor ionotropic, AMPA 2; D002118:Calcium; D016257:Fura-2