摘要
目的研究铅暴露浓度与豚鼠耳蜗毛细胞形态学改变和对听觉系统损害程度的量化关系。方法50只豚鼠分为对照组和实验组。对照组(10只)豚鼠腹腔注射生理盐水1ml,隔日一次。实验组分为两组:高铅组(20只):豚鼠腹腔注射0.25%醋酸铅溶液40mg/kg;低铅组(20只):豚鼠腹腔注射0.25%醋酸铅溶液20mg/kg,分别于停药后7、14、28天采血。断头后行全耳蜗铺片的光学和电镜检查。结果腹腔注射醋酸铅后,血清中铅含量迅速升高。低铅组铅暴露1周后出现外毛细胞损害;高铅组铅暴露2周后外毛细胞损害程度较重,出现细胞变性、减少、结构不清,电镜观察可见毛细胞缺失明显;高铅暴露4周后毛细胞损害呈进行性加重。结论铅暴露对豚鼠耳蜗毛细胞损害明显,表现为纤毛的散乱、倒伏、部分脱落、大片缺失等,其损害程度与铅暴露浓度呈正相关性。
Objective To investigate the quantitative correlations between different levels of lead acetate in exposed guinea pigs and the degree of damage to cochlear hair cells and the auditory system. Methods 50 healthy adult guinea pigs were randomly divided into 3 groups, 10 guinea pigs as the control group, 20 guinea pigs exposed to high dosage in a group and low dosage in another group. For the control group, lml saline was injected into guineapigs abdominal cavity every other day, seven times in total. In the high dosage group, 0.25% lead acetate solution was injected at 40 mg/kg, and in the low dosage group at 20 mg/kg both in the same way compared to the control group. Venous blood samples of all the 3 groups were collected on the 7th, the 14th and the 28th days upon the ces- sion of the drug injection. The cochlear samples were obtained after sacrifice and underwent light microscopic and e- lectron microscopic examinations. Results The lead concentration of the blood the exposed guinea pigs displayed noticeable increase. One week after lead acetate exposure, the out hair cells of the low dosage group were noted to be damaged. The degeneration in the outer hair cells of the high dosage group was found under microscope two weeks after exposure. Four weeks later, the damage to the outer hair cells of the high dosage group became more severe. Conclusion The cochlea in guinea pigs exposed to lead has showed noticeable damage. The missing and scattering of the hair cells were present. There is a strong correction between the duration of lead acetate exposure and the severity of the cochlear damage, indicating the possible impairment to the auditory system under such conditions.
出处
《听力学及言语疾病杂志》
CAS
CSCD
2007年第6期472-474,I0003,共4页
Journal of Audiology and Speech Pathology
关键词
豚鼠
铅暴露
毛细胞
听损伤
Guinea pig
Exposed to lead
Hair cell
Hearing loss
