Yamanobe S, Kanno H
Fukushima Medical University.
Nihon Jibiinkoka Gakkai Kaiho. 1998 Aug;101(8):979-87. doi: 10.3950/jibiinkoka.101.8_979.
We investigated the possibility of ototoxicity induced by deferoxamine mesilate (DFO). DFO was administered to guinea pigs intraperitoneally at 200 or 400 mg/kg body weight/day, 6 days/week for 5 weeks, or 600 mg/kg body weight/day, 6 days/week for 4 weeks. Physiological saline instead of DFO was given to animals as a control. After the course of administration was completed, we measured the threshold of the compound action potential (CAP) and the endocochlear potential (EP). We also examined the cochlear histology by scanning electron microscopy. The CAP threshold of animals treated with 200 or 400 mg of DFO per kg was not elevated. In the animals treated with 600 mg/kg , however, the CAP threshold was clearly elevated when compared with that of control animals. The EP values of animals treated with 200 or 400 mg of DFO per kg were comparable to those of control animals. In some animals treated with 600 mg of DFO per kg, however, the EP values were decreased. Histological examination revealed that the outer hair cells of the cochlea were missing. DFO presumably acts on hair cells, resulting in elevation of the CAP threshold. We concluded that hair cell damage is one of the contributing factors to CAP threshold elevation.
我们研究了甲磺酸去铁胺（DFO）引起耳毒性的可能性。以200或400毫克/千克体重/天的剂量给豚鼠腹腔注射DFO，每周6天，持续5周；或以600毫克/千克体重/天的剂量，每周6天，持续4周。给动物注射生理盐水而非DFO作为对照。给药疗程结束后，我们测量了复合动作电位（CAP）阈值和内耳蜗电位（EP）。我们还通过扫描电子显微镜检查了耳蜗组织学。每千克体重注射200或400毫克DFO的动物的CAP阈值没有升高。然而，在每千克体重注射600毫克的动物中，与对照动物相比，CAP阈值明显升高。每千克体重注射200或400毫克DFO的动物的EP值与对照动物相当。然而，在一些每千克体重注射600毫克DFO的动物中，EP值降低。组织学检查显示耳蜗外毛细胞缺失。DFO可能作用于毛细胞，导致CAP阈值升高。我们得出结论，毛细胞损伤是导致CAP阈值升高的因素之一。
