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Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells
Published on: March 16, 2017
Localization of nitric oxide synthase isoforms in the human cochlea
1Department of Otolaryngology and Head and Neck Surgery, Uppsala University Hospital, Sweden,
Acta Oto-Laryngologica
|August 18, 2001
Summary
Nitric oxide synthase (NOS) I and III are present in the human cochlea, particularly in the spiral ganglion and hair cells. These findings suggest nitric oxide (NO) plays roles in hearing and potential cochlear neurotoxicity.
Area of Science:
- Neuroscience
- Otolaryngology
- Cell Biology
Background:
- The precise localization of nitric oxide (NO) within the cochlea is not fully understood.
- While nitric oxide synthase (NOS) is found in mammalian cochleae, data on human cochlear presence is limited.
Purpose of the Study:
- To investigate the distribution of NOS isoforms I, II, and III within the substructures of the human cochlea.
- To elucidate the potential roles of NO in human cochlear function and pathology.
Main Methods:
- Immunohistochemistry utilizing the fluorescein isothiocyanate technique.
- Application of monoclonal antibodies specific to NOS isoforms I, II, and III.
Main Results:
- NOS I was the predominant isoform, found in spiral ganglion cells, nerve fibers, outer hair cells, organ of Corti supporting cells, and stria vascularis.
- NOS III was observed in outer hair cells, supporting cells, and spiral ganglion cells, but not the stria vascularis.
- NOS II exhibited minimal staining, restricted to a few nerve fibers.
Conclusions:
- NO likely functions as a neurotransmitter or neuromodulator in the human cochlea, impacting neural cells, supporting cells, and the stria vascularis.
- Given its dual role as an excitotoxin and toxic radical, NO may also contribute to neurotoxicity within the human cochlea.
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