Both Central and Peripheral Auditory Systems Are Involved in Salicylate-Induced Tinnitus in Rats: A Behavioral Study

Abstract

ObjectiveThis study was designed to establish a low dose salicylate-induced tinnitus rat model and to investigate whether central or peripheral auditory system is involved in tinnitus.MethodsLick suppression ratio (R), lick count and lick latency of conditioned rats in salicylate group (120 mg/kg, intraperitoneally) and saline group were first compared. Bilateral auditory nerves were ablated in unconditioned rats and lick count and lick latency were compared before and after ablation. The ablation was then performed in conditioned rats and lick count and lick latency were compared between salicylate group and saline group and between ablated and unablated salicylate groups.ResultsBoth the R value and the lick count in salicylate group were significantly higher than those in saline group and lick latency in salicylate group was significantly shorter than that in saline group. No significant changes were observed in lick count and lick latency before and after ablation. After ablation, lick count and lick latency in salicylate group were significantly higher and shorter respectively than those in saline group, but they were significantly lower and longer respectively than those in unablated salicylate group.ConclusionA low dose of salicylate (120 mg/kg) can induce tinnitus in rats and both central and peripheral auditory systems participate in the generation of salicylate-induced tinnitus.

Early cortical metabolic rearrangement related to clinical data in idiopathic sudden sensorineural hearing loss

“…In particular, the authors found that in rats with evidence of tinnitus, activity was generally elevated in the auditory brainstem, with significant elevation in the cerebellar paraflocculus, the posterior ventral cochlear nucleus, and the inferior colliculus (Brozoski et al, 2007). Chen et al reported changes in the cerebellum of rats shortly after tinnitus was induced with a high dose of salicylate (Chen et al, 2014). This evidence could limit the use of the cerebellum for normalization, resulting in a sub-optimal structure for data normalization in certain circumstances and in particular when variations in brain activity in this structure are detectable during tasks or pathological conditions.…”

Central Nervous Activity upon Systemic Salicylate Application in Animals with Kanamycin-Induced Hearing Loss - A Manganese-Enhanced MRI (MEMRI) Study

“…Recent studies have reported that the central auditory system largely contributes to the salicylate-induced effects on neuronal activity and auditory phantom perceptions like tinnitus, even after disconnection of the auditory periphery [ 54 , 75 , 76 ]. In the present data, the calcium-related neuronal activity was increased after systemic application of a sodium salicylate solution in several investigated brain structures.…”

Loss of Cochlear Ribbon Synapse Is a Critical Contributor to Chronic Salicylate Sodium Treatment-Induced Tinnitus without Change Hearing Threshold

“…Previous studies reported that different dosages of SS exposure can trigger tinnitus [17,36]. SS-induced hearing threshold shifts are largely dose-dependent.…”

“…SS, an active component of the nonsteroidal anti-inflammatory drug aspirin, has been commonly used to generate tinnitus in animals [ 17 ]. SS is an anti-inflammation drug used to manage rheumatoid arthritis at therapeutic dose; SS inhibits cyclooxygenase activity and prostaglandin synthesis.…”