Lee Jong Joo, Jang Jeong Hun, Choo Oak-Sung, Lim Hye Jin, Choung Yun-Hoon
Department of Otolaryngology, Ajou University School of Medicine, Suwon, Republic of Korea.
Soree Ear Clinic, Seoul, Republic of Korea.
Laryngoscope. 2018 Jan;128(1):189-194. doi: 10.1002/lary.26562. Epub 2017 Mar 17.
Steroids have been widely used to treat inner-ear diseases such as sudden sensorineural hearing loss, tinnitus, and Meniere's disease. They can be given via either systemic or intratympanic (IT) injection. The purpose of the present study was to explore differences in intracochlear steroid distribution by the administration method employed (systemic vs. IT injection).
Animal study.
Twenty-three Sprague-Dawley rats were given fluorescein isothiocyanate-labeled dexamethasone (FITC-DEX) three times (on successive days) via intraperitoneal (IP) or IT injection. Cochlear uptake of FITC-DEX was evaluated via immunohistochemistry and flow cytometry at 6 hours, and 3 and 7 days after the final injection.
FITC-DEX uptake was evident in spiral ganglion cells (SGs), the organ of Corti (OC), and the lateral walls (LWs), the basal turns of which were stained relatively prominently in both groups. Animals receiving IP injections exhibited higher FITC-DEX uptakes by the SGs and OC, whereas IT injection triggered higher-level FITC-DEX accumulation by the OC and LWs. Flow cytometry revealed that intracochlear FITC-DEX uptake by IT-injected animals was higher and more prolonged than in animals subjected to IP injections.
We thus describe differences in cochlear steroid distributions after systemic and IT injections. This finding could help our understanding of the pharmacokinetics of steroids in the cochlea.
NA. Laryngoscope, 128:189-194, 2018.
类固醇已被广泛用于治疗内耳疾病，如突发性感音神经性听力损失、耳鸣和梅尼埃病。它们可以通过全身给药或鼓室内（IT）注射。本研究的目的是探讨采用不同给药方法（全身给药与IT注射）时耳蜗内类固醇分布的差异。
动物研究。
23只Sprague-Dawley大鼠通过腹腔内（IP）或IT注射，连续三天给予异硫氰酸荧光素标记的地塞米松（FITC-DEX）。在最后一次注射后的6小时、3天和7天，通过免疫组织化学和流式细胞术评估耳蜗对FITC-DEX的摄取情况。
FITC-DEX在螺旋神经节细胞（SGs）、柯蒂氏器（OC）和侧壁（LWs）中摄取明显，两组动物中这些结构的基底转染色相对较深。接受IP注射的动物，SGs和OC对FITC-DEX的摄取较高，而IT注射则使OC和LWs中FITC-DEX的积累水平更高。流式细胞术显示，与接受IP注射的动物相比，接受IT注射的动物耳蜗内FITC-DEX的摄取更高且持续时间更长。
因此，我们描述了全身给药和IT注射后耳蜗类固醇分布的差异。这一发现有助于我们理解类固醇在耳蜗中的药代动力学。
NA。《喉镜》，2018年，第128卷，第189 - 194页。
