水杨酸钠诱导大鼠耳鸣模型的双重行为与电生理评估：比较听性脑干反应中的短声与啁啾声刺激。

文献信息

中文摘要

背景： 动物模型对于研究耳鸣生理学和治疗干预至关重要。本研究旨在采用行为-电生理双重方法评估水杨酸钠诱导的耳鸣大鼠模型，并比较听性脑干反应（ABR）中短声和啁啾声刺激的敏感性。方法：在水T迷宫（WTM）中进行声音-静音条件化后，水杨酸组接受水杨酸钠（300mg/kg，腹腔注射）六天，而假手术组接受0.9%生理盐水。通过水T迷宫游泳测试行为学评估耳鸣存在，随后在麻醉下使用80dB SPL的短声和啁啾声刺激（波I-V）以及20dB SPL（波II用于听力损失评估）进行ABR记录。结果：分析了24只听力正常的雄性Sprague-Dawley大鼠，分为假手术组（n=13）和水杨酸组（n=11）。行为学上，水杨酸组大鼠在静音期间在声音关联臂停留的时间显著更长，表现出耳鸣样行为。电生理学上，水杨酸钠给药仅在短声诱发的ABR中引起波III振幅显著增加。相反，啁啾声诱发的ABR振幅在水杨酸暴露后未见改变。在潜伏期分析中，虽然三因素交互作用不显著。刺激×时间两因素交互作用仅在波V中具有统计学显著性。结论：将水T迷宫测试与ABR记录相结合，为评估实验性耳鸣提供了一种省时且符合动物福利的方法。在本记录条件下，短声诱发的ABR在该特定急性模型中比啁啾声刺激更敏感地捕捉到振幅变化，尽管在短声刺激被确立为耳鸣评估的普遍优越标志物之前，还需要进一步研究。

英文摘要

Animal models are essential for investigating tinnitus physiology and therapeutic interventions. This study aimed to evaluate a salicylate-induced tinnitus rat model using a dual behavioral-electrophysiological approach and to compare the sensitivity of click and chirp stimuli in auditory brainstem responses (ABRs). Following sound-silence conditioning in a water T-maze (WTM), the salicylate group received sodium salicylate (300mg/kg, i.p.) for six days, while the sham group received 0.9% saline. Tinnitus presence was behaviorally assessed via the water T maze swimming test, followed by ABR recordings under anesthesia using click and chirp stimuli at 80dB SPL (waves I-V) and 20dB SPL (wave II for hearing loss evaluation). Twenty-four male Sprague-Dawley rats with normal hearing were analyzed to sham (n=13) and salicylate (n=11) groups. Behaviorally, rats in the salicylate group spent significantly more time in the sound-associated arm during silence, demonstrating tinnitus-like behavior. Electrophysiologically, salicylate administration induced significant amplitude increases in waves III exclusively in click-evoked ABRs. Conversely, chirp-evoked ABR amplitudes showed no alterations post-salicylate exposure. In the latency analyses, while the three-way interaction was not significant. The stimulus x time two-way interaction was found to be statistically significant only for wave V. In conclusion, combining Water T-Maze testing with ABR recordings offers a time-efficient and animal-welfare-oriented approach to evaluate experimental tinnitus. Under the present recording conditions, click-evoked ABRs captured amplitude alterations more responsively than chirp stimuli in this specific acute model, though further research is required before click stimuli can be established as a generally superior marker for tinnitus assessment.