缓释载药体泊洛沙姆407圆窗灌注对耳蜗结构与听觉功能的影响

目的观察圆窗局部灌注泊洛沙姆407对耳蜗功能和结构的影响。方法16只健康豚鼠右耳圆窗灌注100μl20％泊洛沙姆407溶液作为实验组,左耳灌注生理盐水作为对照组,另取4只动物不予处理作为阴性对照组。于灌注前、后及灌注后第7、14、28及49d行听性脑干诱发电位（auditorybrainstemresponse,ABR）检测,并于检测后分别处死4只动物,行耳蜗基底膜铺片并计数。结果泊洛沙姆407灌注后ABR阈值较灌注前均有所提高,但在49d时恢复至灌注前水平;耳蜗毛细胞计数显示泊洛沙姆407圆窗灌注后无明显毛细胞缺失。结论泊洛沙姆407圆窗灌注对ABR阈值有暂时性影响,但未对耳蜗功能和结构起到持久性不可逆性损伤,符合中、内耳疾病的缓释给药治疗的条件。

Effect of poloxamer 407 on the cochlear morphology and hearing function after perfusion in round window: experiment with guinea pigs

OBJECTIVE: To observe the effect of sustained-release vehicle-Poloxamer 407 on the function and morphology of the cochlear after perfusion in round window. METHODS: The right ears of 16 guinea pigs as experimental group were perfusion with 20% Poloxamer 407 solusion 100 microl in round window, the left ears as control group with normal saline. Another 4 animals without treatment were in negative control group. Auditory function was investigated before and immediate, 7, 14, 28, 49 days after perfusion, and the cochlear basilar membranes were stained by silver nitrate after ABR examinations. The stained basilar membranes were examined under light microscopy. RESULTS: The ABR threshold to filtered clicks were elevated after perfusion, and were recovered to normal at 49 days after perfusion. The morphology of cochlear hair cells were not significantly damaged after perfusion. CONCLUSION: Poloxamer 407 after topical perfusion in round window can cause temporary changes on auditory function of inner ear, but no inreversible damage on function and morphology of cochlear. Therefore, Polomamer 407 can be used as sustained-release vehicle in middle and inner ear diseases.