18-β甘草次酸对变应性鼻炎大鼠鼻黏膜上皮细胞内质网的影响

Effect of 18-β Glycyrrhetinic Acid on the Endoplasmic Reticulum of Nasal Epithelial Cells in Allergic Rhinitis Model Rats

目的探讨18-β甘草次酸(glycyrrhetinic acid,GA)对变应性鼻炎(allergic rhinitis,AR)模型大鼠鼻黏膜上皮细胞内质网变化的影响。方法 96只Wistar大鼠随机分为空白组、AR模型组、氯雷他定组、甘草次酸组,每组24只,腹腔注射卵清蛋白致敏建立大鼠AR模型,评定动物形态学评分。造模后给予甘草次酸21.6 mg/kg灌胃,干预后第2、4、6、10周取鼻黏膜组织送电镜检查。结果空白组叠加评分(2.10±0.45)分,氯雷他定组为(5.10±0.56)分,AR模型组为(5.10±0.56)分,甘草次酸组为(5.20±0.78)分,各组分别与空白组比较,差异有统计学意义(P<0.01)。透射电镜见AR模型组内质网较空白组增多,明显囊样扩张、大量空泡形成、脱颗粒,胞质内可见大量的游离核糖体。在变应原持续作用下,AR模型组鼻黏膜上皮细胞内质网的上述变化呈进行性加重。而甘草次酸干预组内质网扩张、空泡化、脱颗粒均较模型组缓解,并随观察周期延长逐渐接近空白对照组。结论 18-β甘草次酸可改善变应性鼻炎模型大鼠鼻黏膜上皮细胞内质网的扩张、空泡化及脱颗粒。

Objective To explore the effect of 18-β glycyrrhetinic acid （GA） on the endoplasmic reticulum of nasal epithelial cells in allergic rhinitis （AR） model rats. Methods Totally 96 Wistar rats were randomly divided into the blank group, the AR model group, the Ioratadine group, the GA group, 24 in each group. AR models were established by peritoneally injecting ovalbumin （OVA）. Morphological scoring was performed. GA at 21.6 mg/kg was intragastrically administered to rats in the GA group. Nasal mucosal tissues were taken for electron microscopic examinations at the second, fourth, sixth, and tenth week after drug intervention. Results The overlapping score was 2.10 ±0.45 in the blank group, 5.10±0.56 in the Ioratadine group, 5.10±0.56 in the AR model group, 5.20 ±0.78 in the GA group, showing statistical difference when compared with the blank group （P 〈0.01 ）. Results under transmission electron microscope showed that the number of the endoplasmic reticulum increased in the AR mod- el group, with obvious cystic dilatation, a lot of vacuole formation, and degranulation. A large number of free ribosomes could be seen in cytoplasm. With persistent allergen exposure, changes mentioned above was progressively aggravated in the endoplasmic reticulum of nasal mucosal epithelium in the AR model group. But the dilation of endoplasmic reticulum, vacuole formation, and degranulation were relieved in the GA group, and got close to those of the blank group. Conclusion 18-β GA could improve the expansion, vacuolization, and degranulation of the endoplasmic reticulum of nasal epithelial cells in AR model rats.