Padmanabhan R, Singh S
Acta Anat (Basel). 1984;119(4):217-23. doi: 10.1159/000145888.
A single dose of cyclophosphamide (20 mg/kg) administered on day 12 of gestation to CF rats resulted in microtia in 97.5% of fetuses at term. The ears of affected fetuses were low set and dorsally placed. Histological examination revealed persistence of meatal plug, branching of the primordium of external acoustic meatus, periotic hemorrhages, narrowing of tympanic cavity, presence of only one to two primordia of middle ear ossicles, hypoplasia of stapedial artery, a maximum of two turns of cochlea and under differentiation of the organ of Corti and the semicircular ducts. Hemorrhages in and around the region of the ear were extensive. Bilaterally symmetrical distribution of microtia and consistency of associated anomalies suggest that this is a good animal model for further investigation into the pathogenetic mechanisms of these ear anomalies.
在妊娠第12天给CF大鼠单次注射环磷酰胺（20mg/kg），足月时97.5%的胎儿出现小耳畸形。受影响胎儿的耳朵位置低且靠背部。组织学检查显示耳道栓持续存在、外耳道原基分支、耳周出血、鼓室狭窄、中耳听小骨仅一至两个原基、镫骨动脉发育不全、耳蜗最多两圈以及柯蒂氏器和半规管分化不全。耳部区域及其周围出血广泛。小耳畸形的双侧对称分布以及相关异常的一致性表明，这是进一步研究这些耳部异常发病机制的良好动物模型。
