卡铂引起的毛细胞四种酶的活性改变

Mechanisms of Carboplatin Ototoxicity Suggested by Cytochemical Analysis

目的 探讨卡铂的耳毒性机理。方法 ８ 只灰鼠中５ 只按１００ ｍｇ／ｋｇ 腹腔注射卡铂，３ 只作正常对照，注药后４８ 小时处死。对分离的耳蜗基底膜进行了不同的细胞化学染色，反应结果在透射电镜下观察。结果 与对照耳相比，卡铂组的内毛细胞显示钙离子激活的ＡＴＰ 酶活性增强，而钠钾离子激活的ＡＴＰ 酶、碱性磷酸酶和葡萄糖－ ６ － 磷酸酶的活性降低；外毛细胞则显示钙离子激活的ＡＴＰ 酶和碱性磷酸酶的活性增强，葡萄糖－ ６ － 磷酸酶的活性降低，而钠钾离子激活的ＡＴＰ 酶无明显改变。

Objective To examine the mechanisms of carboplatin ototoxicity.Methods Forty- eight hours following administration of Carboplatin(100 mg/kg),5 Carboplatin-treated chinchillas, together with 3controls,were sacrificed.After dissection of the organ of Corti,the samples were processed for a series of cytochemical staining,and observed under transmission electron microscopy.Results Compared to normal ears, the Carboplatin-treated ears showed increased Ca ++ -ATPase,decreased Na +K +-ATPase,alkaine phosphatase and glucose-6-phosphatase activities in inner cells.The outer hair cells,however,incurred increased activities of Ca ++ ATPase and alkaline phosphatase,decreased activity of glucose-6-phosphatase with unchanged activity in Na +K + ATPase.Conclusion The results suggest that the released calcium may result in ion inbalance and impediment of energy metabolism.