Role of the caudate-putamen nucleus in sensory gating in induced tinnitus in rats

Tinnitus can be described as the conscious perception of sound without external stimulation, and it is often accompanied by anxiety, depression, and insomnia. Current clinical treatments for tinnitus are ineffective. Although recent studies have indicated that the caudate-putamen nucleus may be a sensory gating area involved in noise elimination in tinnitus, the underlying mechanisms of this disorder are yet to be determined. To investigate the potential role of the caudate-putamen nucleus in experimentally induced tinnitus, we created a rat model of tinnitus induced by intraperitoneal administration of 350 mg/kg sodium salicylate. Our results revealed that the mean spontaneous firing rate of the caudate-putamen nucleus was increased by sodium salicylate treatment, while dopamine levels were decreased. In addition, electrical stimulation of the caudate-putamen nucleus markedly reduced the spontaneous firing rate of neurons in the primary auditory cortex. These findings suggest that the caudate-putamen nucleus plays a sensory gating role in sodium salicylate-induced tinnitus. This study was approved by the Institutional Animal Care and Use Committee of Peking University Health Science Center (approval No. A2010031) on December 6, 2017.