Candidate's Thesis: Platelet‐Activating Factor–Induced Hearing Loss: Mediated by Nitric Oxide?

Abstract

This study demonstrated that PAF placed on the RWM induced hearing loss and cochlear hair cell damage. The PAF-antagonists and L-NAME prevented the PAF-induced hearing loss and inhibited iNOS expression in the cochlea. These findings suggest that the PAF-induced hearing loss caused by cochlear hair cell damage may have been mediated by NO. PAF-antagonists and L-NAME may have future therapeutic implications in preventing sensorineural hearing loss associated with chronic otitis media. The results of this study have significant potential clinical application.

Genetics of guanylyl cyclase pathways in the cochlea and their influence on hearing

“…In contrast to these scattered reports for the constitutive forms of NOS, upregulation of iNOS has been demonstrated in many forms of cochlear pathology, including hearing loss due to hypoxia (94,191,205,311), middle ear infection (248,276,319), inflammation (109,204,213,303,306,331), and Ménière disease (120,121,198). Increases in iNOS activity have been observed in the stria vascularis following administration of many ototoxins, including cisplatin (164,320,321), gentamycin (274), aminoglycosides (169), and carbon monoxide (41).…”

Effects of Tumor Necrosis Factor Alpha Antagonist, Platelet Activating Factor Antagonist, and Nitric Oxide Synthase Inhibitor on Experimental Otitis Media with Effusion

“…in purulent MEEs. 6 Rhee et al 4 Platelet activating factor is a potent mediator of neutrophil activation leading to calcium mobilization, chemotaxis, aggregation, degranulation, and Mean thickness of middle ear mucosa. Middle ear mucosa ofLPS group was significantly thicker than those of2 control groups.…”

“…It can cause pathological changes, including mucosal hyperplasia, bone erosion, fibrosis, and hearing loss. [4][5][6] For the treatment of MEE, Jeon et al? and Lee et al 8 demonstrated that an inhibitor of TNF-a, TNF soluble receptor type I (sTNFRI), prevents experimental otitis media with effusion (OME).…”

“…Fig6. Mean counts (cells per 100 lattices) of inflammatory cells infiltrated in subepithelial layer of promontory mucosa.…”