Nerve fibers exposed to SS showed fragmentation, blebs, and breaks that enhanced with the concentration of SS. The imply cochleograms in Figure 4-B shows the percentages of missing OHC and IHC in handle cultures and cultures treated with three, 5 orFig. 4. (A) SGN fibres from the middle turn from the cochlea immunolabelled with principal antibody against -tubulin and secondary antibody conjugated to Alexa Fluor 488 in handle cultures and in three, five and 10 mM SS for 96 hours. In control cultures, nerve fibres demonstrate thick healthful fascicles. With increasing concentrations of SS the nerve fibres show increasingly much more fragmentations and blebs (white arrows), and in the end nerve fiber disappearance inside a dose dependent manner. Image obtained from Deng 2013, with permission. (B) Cochleogram representing the percentage of GIT 27 sensory cell loss in control cultures and cultures treated with 3, five and ten mM SS for 48 hours. SGN fibres are degenerated when exposed to SS inside a dose dependent manner; even so, sensory cells seem structurally unaffected.A. Sheppard et al.10 mM SS. These final results indicate that even the highest dose of SS does not destroy hair cells six. In addition, current in vivo studies indicate that high doses of SS can lead to SGN degeneration by means of caspase-mediated apoptosis 40. Paradoxically, salicylate is really a potent antioxidant with neuro- and oto-protective properties 41 42. On the other hand, high doses of salicylate result in an upsurge with the very toxic superoxide radical in SGNs but not neighbouring sensory and supporting cells six. Little or no dihydroethidium (DHE) staining, which labels the superoxide radical, was observed in manage cultures. In cochlear cultures treated with ten mM SS for 48 hours, a considerable volume of DHE staining was observed in SGNs, but not in neighbouring sensory or support cells 6. When cultures have been treated with ten mM SS plus 100 PyP, a cell permeable superoxide scavenger, they showed substantially significantly less SGN damage than these treated with SS alone 6. Therefore, for factors however unknown, high doses of SS exert their toxic effects on SGN by selectively increasing the production from the superoxide radical in SGN, but not other cells within the inner ear. Auditory Nerve (AN) Auditory nerve fibre recordings following higher doses of SS treatment have yielded variable results, which could possibly be a result in the dosage, route of administration or species differences. In cats, a considerable improve in spontaneous auditory nerve firing was observed following an exceptionally higher dose of SS (400 mg/kg, i.v.) 43. In contrast, in gerbils, a slight but substantial reduction in auditory nerve firing rate following a moderate dose of SS (200 mg/kg i.p.) was observed in fibres with low characteristic frequencies (CFs), but not in fibres with higher CFs 44. Nonetheless, cross comparisons in between these species is unreliable because of the cats’ inability to proficiently metabolise salicylate 45 46. The effects of chronic therapy of salicylate on spontaneous auditory nerve activity has also been evaluated 47. The average spectrum of electrophysiological cochleoneural activity (ASECA), a measurement of auditory nerve activity, was recorded from the round window in guinea pigs over various weeks of salicylate administration (200 mg/ kg/day, i.m.).