电离辐射对中耳黏膜杯状细胞的影响

[目的]通过动物模型研究中耳黏膜辐射损伤产生放射性中耳炎的病理改变和机制.[方法]30只豚鼠作为实验对象,模仿临床放射治疗过程,以钴60产生的放射线照射中耳制作放射性中耳炎模型.γ射线照射右耳,300cGy/f,5次/周.实验动物分5组:0、15Gy、30Gy、45Gy、45Gy照射后30d,观察各组动物照射侧中耳黏膜杯状细胞的变化.[结果]中耳黏膜上皮在15Gy组无明显变化.30Gy组,咽鼓管及近咽鼓管鼓室口处黏膜水肿、增厚,杯状细胞明显增加.45Gy组和45Gy照射后30d组咽鼓管及近咽鼓管鼓室口处黏膜与正常组比较明显增厚,杯状细胞明显增加,而鼓岬部黏膜缺乏杯状细胞,放射前后未发现变化.[结论]在放射治疗早期,随着放射剂量的增加,咽鼓管及近咽鼓管鼓室口处黏膜杯状细胞明显增加,增加的杯状细胞将引起黏液的分泌增加,其与放射所致纤毛功能损害共同导致咽鼓管功能损害,引起渗出性中耳炎并使之加重.

Impact of Irradiation on Middle Ear Mucosa Goblet Cells

[Purpose] To investigate the density of the mucus-producing goblet cells in the middle ear and Eustachian tube during and after irradiation. [Methods] Adult guinea pigs(n=30) were used in this study. Gamma irradiation was administered to the right ear of each guinea pig with 300cGy/fraction, 5 times per week using a cobalt-60 machine. Every six animals were then sacrificed when the total dose reached 15Gy, 30Gy, 45Gy respectively. Six animals were killed thirty days after having been administered 45Gy and six untreated were selected as control group. The changes of goblet cells of middle ear mucosa were observed using light microscope after Periodic acid Schiff/Alcian blue staining. [Results] The goblet cells was increased after having administered 30Gy and having administered 45Gy in the tympanic mucosa near the orifice, and but lack of goblet cells in the tube. Whereas no changes were registered in the mucosa of the promontory. [Conclusions] The goblet cells in the Eustachian tube and the tympanic mucosa near the orifice is increased with the increasing dose of irradiation in the early stage. It indicated that excessive secretion with increase goblet cells may contribute to the deteriorated Eustachian tube function following irradiation, and may aggravate middle ear disease.