目标:耳鸣,幻影声音的产生,可能是噪声暴露的结果,然而,对其潜在机制的理解是有限的。研究的目的是确定不同浓度的水杨酸盐是否会引起不同强度的耳鸣。
方法:为了本研究的目的,使用50只雄性Wistar大鼠。将动物分成5组(每组10只大鼠)。未接受任何物质的动物被分配到对照组(A组)。第二组(B组)大鼠腹膜内接受水杨酸盐(SigmaAldrich)7天(300mg/Kg/天)。第3组(C组)腹腔注射水杨酸盐7天,但浓度为第二组动物的两倍(600mg/kg/d)。第4组(D组)同时接受水杨酸盐(300mg/Kg/天)和纯美金刚(SigmaAldrich,10mg/kg/d)腹腔内连续7天。第5组(E组)未接受任何物质,但连续168小时(7天)暴露于声音以诱发耳鸣。使用失真产物耳声发射(DPOAEs)评估耳蜗活动。在实验期结束时,动物被处死,并取出右侧耳蜗,准备进一步的组织学和免疫组织化学研究。
结果:用水杨酸盐单药治疗或水杨酸盐联合美金刚治疗的动物的DPOAE与本底噪声没有区别,与对照组的动物或暴露于恒定噪音的动物相比,没有显着差异。E组的耳蜗结构在解剖学和功能上不受暴露于恒定噪声的影响。美金刚似乎对耳蜗结构没有实质性的保护,根据组织学检查和听力测试,然而,接受它的大鼠在行为测试中表现出更好的结果。
结论:施用美金刚对耳鸣的减少没有显著贡献。
OBJECTIVE: Tinnitus, the generation of phantom sounds, can be the result of noise exposure, however, understanding of its underlying mechanisms is limited. Purpose of the study was is to determine whether different concentrations of salicylate can cause tinnitus of different intensity.
METHODS: For the purposes of this study 50 male Wistar rats were used. The animals were divided into 5 groups (10 rats in each group). The animals that did not receive any substance were allocated to the control group (Group A). The second group (Group B) of rats received salicylate (Sigma Aldrich) intraperitoneally for 7 days (300 mg/Kg/day). The 3rd group (Group C) received salicylate intraperitoneally for 7 days, but at twice the concentration of the animals in the second group (600 mg/kg/d). The 4th group (Group D) simultaneously received salicylate (300 mg/Kg/day) and pure Memantine (Sigma Aldrich, 10 mg/kg/d) intraperitoneally for 7 days. The 5th group (Group E) did not receive any substance but was exposed for 168 consecutive hours (7 days) to sound to induce tinnitus. Cochlear activity was evaluated with the use of Distortion Product Otoacoustic Emissions (DPOAEs). At the end of the experimental period, the animals were sacrificed, and the right cochlea was removed and prepared for further histological and immunohistochemical studies.
RESULTS: The DPOAEs of animals treated either with salicylate as monotherapy or salicylate combined with memantine were indistinguishable from the noise floor, did not differ significantly compared to the animals of the control group or those expose to constant noise. The cochlear structures of Group E remained anatomically and functionally unaffected from the exposure to constant noise. Memantine does not seem to offer substantial protection to the cochlear structures, according to histological examination and hearing tests, however, the rats receiving it exhibited better results in behavioral tests.
CONCLUSIONS: The administration of memantine does not contribute significantly to the reduction of tinnitus.