山莨菪碱对耳蜗辐射防护作用的动物实验研究

Experimental Study on the Protective Effect of Anisodamine on Radiational Damage of the Cochlea

目的研究山莨菪碱对耳蜗辐射损伤的防护作用。方法健康豚鼠25只随机分成三组:对照组、单纯放射组和山莨菪碱防护组,每组观察10耳。放疗前30分钟,按每公斤体重20mg于山莨菪碱防护组豚鼠的股部肌肉注射山莨菪碱,对照组和单放组在上述部位注射等量生理盐水。用直线加速器所产生的6Mev电子线对山莨菪碱防护组和单纯放射组豚鼠的耳颞部予以分次照射,总剂量达到60Gy后作耳蜗毛细胞的光镜及扫描电镜观察。结果耳蜗基底膜铺片表明对照组照射耳耳蜗内外毛细胞排列整齐无缺如,单纯放疗组照射耳耳蜗外毛细胞有大量缺如,内毛细胞有少许缺如,山莨菪碱防护组照射耳耳蜗外毛细胞少许缺如,内毛细胞无缺如;扫描电镜表明对照组照射耳耳蜗外毛细胞的纤毛排列整齐无倒伏、缺失,单纯放疗组照射耳耳蜗外毛细胞的纤毛明显倒伏、缺失、排列紊乱,山莨菪碱防护组照射耳耳蜗外毛细胞的纤毛排列基本整齐,偶见倒伏现象。结论①分割剂量60Gy对豚鼠耳颞部照射可造成耳蜗毛细胞损害,②山莨菪碱对耳蜗辐射损伤具有保护作用。

Objective To evaluate the protective effect of anisodamine on radiational damage of the cochlea. Methods 25 guinea pigs were randomly divided into 3 groups： control group, radiation group and anisodamine protection group. 10 ears of each group were observed. 30 minutes before radiotherapy, 20rag anisodamine per kilogramme in body weight was intramuscularly injected into the thighs of the guinea pigs in the anisodamine protection group. The control group and radiation group were treated with physiologic saline respectively with the same dose as anisodamine. 6 Mev electron ray produced by a accelerator linear was used to irradiate the tempuses of the guinea pigs in the anisodamine protection group and radiation group fractionally. Cochlea hair cells were observed through light microscope and scanning electron microscope when the accumulative dose added up to 60 Gy. Results Stretched preparations of cochlea basilar membrane indicated that the cochlea outer fair cells and inner hair cells in control group remained intact and arranged in order. But in the radiation group, cochlea outer fair cells reduced greatly in quantity and inner hair cells reduced a few. But the cochlea outer fair cells in the anisodamine protection group were lost in a small amount and no reduction of inner hair cells was found. Scanning electron microscope showed that no collapse and reduction were found in the cochlea outer fair cells in the control group but that in the radiation group collapsed , reduced in number and were in a state of chaos , while inner and outer cells in the anisodamine protection group arranged regularity on the whole and the collap- ses were found occasionally. Conclusions The 60 - Gy radiation in fractional doses on the tempuses of the guinea pigs can damage the hair cells of the guinea pigs and anisodamine has protective effect on the cochlea which suffers from irradiation.