Huang C C, Shi G S, Yi Z X
Department of Otolaryngology, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Am J Otolaryngol. 1988 Jul-Aug;9(4):165-72. doi: 10.1016/s0196-0709(88)80024-3.
We induced cholesteatoma in two groups of rats by instilling different concentrations of propylene glycol into the middle ear cavity. Fifteen rats were exposed to 50% propylene glycol (group I), while pure propylene glycol was applied to six others (group II). The group I rats were killed 1 month after instillation. Seven of the 15 showed cholesteatoma in the middle ear with accumulation of keratin debris. The group II rats were killed 3 months after instillation. All six animals showed inflammation in the experimental ears, and five of the six experimental ears showed cholesteatoma in the middle ear cavity. Six experimental ears in group I and five in group II revealed retraction of the tympanic membrane, possibly due to eustachian tube obstruction. Bone resorption was seen along with cholesteatoma and inflammatory cells and osteoclasts in the middle ear of all 11 of these rats. The seventh cholesteatoma of group I can be classified as a microcholesteatoma, a pearl-like cyst within the tympanic membrane. The microcholesteatoma was formed by an invasion of basal cells from the tympanic epidermis and the proliferation of these cells in the fibrous layer of the tympanic membrane. Our findings suggest that cholesteatoma in the middle ear cavity is a response to the inflammation produced by high concentrations of propyleme glycol.
我们通过向两组大鼠的中耳腔滴注不同浓度的丙二醇来诱发胆脂瘤。15只大鼠暴露于50%的丙二醇中（第一组），另外6只则滴注纯丙二醇（第二组）。第一组大鼠在滴注后1个月处死。15只中有7只在中耳出现胆脂瘤，伴有角蛋白碎屑堆积。第二组大鼠在滴注后3个月处死。所有6只动物的实验耳均出现炎症，6只实验耳中有5只在中耳腔出现胆脂瘤。第一组的6只实验耳和第二组的5只实验耳出现鼓膜内陷，可能是由于咽鼓管阻塞所致。在所有这11只大鼠的中耳中，胆脂瘤、炎性细胞和破骨细胞均伴有骨质吸收。第一组的第7个胆脂瘤可归类为微胆脂瘤，即鼓膜内的珍珠样囊肿。微胆脂瘤是由鼓膜表皮的基底细胞侵入以及这些细胞在鼓膜纤维层中的增殖形成的。我们的研究结果表明，中耳腔胆脂瘤是对高浓度丙二醇产生的炎症的一种反应。
